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#ifndef AMD_VULKAN_MEMORY_ALLOCATOR_H
#define AMD_VULKAN_MEMORY_ALLOCATOR_H
#ifdef __cplusplus
extern "C" {
#endif
/** \mainpage Vulkan Memory Allocator
<b>Version 2.3.0-development</b> (2019-03-05)
Copyright (c) 2017-2018 Advanced Micro Devices, Inc. All rights reserved. \n
License: MIT
Documentation of all members: vk_mem_alloc.h
\section main_table_of_contents Table of contents
- <b>User guide</b>
- \subpage quick_start
- [Project setup](@ref quick_start_project_setup)
- [Initialization](@ref quick_start_initialization)
- [Resource allocation](@ref quick_start_resource_allocation)
- \subpage choosing_memory_type
- [Usage](@ref choosing_memory_type_usage)
- [Required and preferred flags](@ref choosing_memory_type_required_preferred_flags)
- [Explicit memory types](@ref choosing_memory_type_explicit_memory_types)
- [Custom memory pools](@ref choosing_memory_type_custom_memory_pools)
- [Dedicated allocations](@ref choosing_memory_type_dedicated_allocations)
- \subpage memory_mapping
- [Mapping functions](@ref memory_mapping_mapping_functions)
- [Persistently mapped memory](@ref memory_mapping_persistently_mapped_memory)
- [Cache control](@ref memory_mapping_cache_control)
- [Finding out if memory is mappable](@ref memory_mapping_finding_if_memory_mappable)
- \subpage custom_memory_pools
- [Choosing memory type index](@ref custom_memory_pools_MemTypeIndex)
- [Linear allocation algorithm](@ref linear_algorithm)
- [Free-at-once](@ref linear_algorithm_free_at_once)
- [Stack](@ref linear_algorithm_stack)
- [Double stack](@ref linear_algorithm_double_stack)
- [Ring buffer](@ref linear_algorithm_ring_buffer)
- [Buddy allocation algorithm](@ref buddy_algorithm)
- \subpage defragmentation
- [Defragmenting CPU memory](@ref defragmentation_cpu)
- [Defragmenting GPU memory](@ref defragmentation_gpu)
- [Additional notes](@ref defragmentation_additional_notes)
- [Writing custom allocation algorithm](@ref defragmentation_custom_algorithm)
- \subpage lost_allocations
- \subpage statistics
- [Numeric statistics](@ref statistics_numeric_statistics)
- [JSON dump](@ref statistics_json_dump)
- \subpage allocation_annotation
- [Allocation user data](@ref allocation_user_data)
- [Allocation names](@ref allocation_names)
- \subpage debugging_memory_usage
- [Memory initialization](@ref debugging_memory_usage_initialization)
- [Margins](@ref debugging_memory_usage_margins)
- [Corruption detection](@ref debugging_memory_usage_corruption_detection)
- \subpage record_and_replay
- \subpage usage_patterns
- [Simple patterns](@ref usage_patterns_simple)
- [Advanced patterns](@ref usage_patterns_advanced)
- \subpage configuration
- [Pointers to Vulkan functions](@ref config_Vulkan_functions)
- [Custom host memory allocator](@ref custom_memory_allocator)
- [Device memory allocation callbacks](@ref allocation_callbacks)
- [Device heap memory limit](@ref heap_memory_limit)
- \subpage vk_khr_dedicated_allocation
- \subpage general_considerations
- [Thread safety](@ref general_considerations_thread_safety)
- [Validation layer warnings](@ref general_considerations_validation_layer_warnings)
- [Allocation algorithm](@ref general_considerations_allocation_algorithm)
- [Features not supported](@ref general_considerations_features_not_supported)
\section main_see_also See also
- [Product page on GPUOpen](https://gpuopen.com/gaming-product/vulkan-memory-allocator/)
- [Source repository on GitHub](https://github.com/GPUOpen-LibrariesAndSDKs/VulkanMemoryAllocator)
\page quick_start Quick start
\section quick_start_project_setup Project setup
Vulkan Memory Allocator comes in form of a "stb-style" single header file.
You don't need to build it as a separate library project.
You can add this file directly to your project and submit it to code repository next to your other source files.
"Single header" doesn't mean that everything is contained in C/C++ declarations,
like it tends to be in case of inline functions or C++ templates.
It means that implementation is bundled with interface in a single file and needs to be extracted using preprocessor macro.
If you don't do it properly, you will get linker errors.
To do it properly:
-# Include "vk_mem_alloc.h" file in each CPP file where you want to use the library.
This includes declarations of all members of the library.
-# In exacly one CPP file define following macro before this include.
It enables also internal definitions.
\code
#define VMA_IMPLEMENTATION
#include "vk_mem_alloc.h"
\endcode
It may be a good idea to create dedicated CPP file just for this purpose.
Note on language: This library is written in C++, but has C-compatible interface.
Thus you can include and use vk_mem_alloc.h in C or C++ code, but full
implementation with `VMA_IMPLEMENTATION` macro must be compiled as C++, NOT as C.
Please note that this library includes header `<vulkan/vulkan.h>`, which in turn
includes `<windows.h>` on Windows. If you need some specific macros defined
before including these headers (like `WIN32_LEAN_AND_MEAN` or
`WINVER` for Windows, `VK_USE_PLATFORM_WIN32_KHR` for Vulkan), you must define
them before every `#include` of this library.
\section quick_start_initialization Initialization
At program startup:
-# Initialize Vulkan to have `VkPhysicalDevice` and `VkDevice` object.
-# Fill VmaAllocatorCreateInfo structure and create #VmaAllocator object by
calling vmaCreateAllocator().
\code
VmaAllocatorCreateInfo allocatorInfo = {};
allocatorInfo.physicalDevice = physicalDevice;
allocatorInfo.device = device;
VmaAllocator allocator;
vmaCreateAllocator(&allocatorInfo, &allocator);
\endcode
\section quick_start_resource_allocation Resource allocation
When you want to create a buffer or image:
-# Fill `VkBufferCreateInfo` / `VkImageCreateInfo` structure.
-# Fill VmaAllocationCreateInfo structure.
-# Call vmaCreateBuffer() / vmaCreateImage() to get `VkBuffer`/`VkImage` with memory
already allocated and bound to it.
\code
VkBufferCreateInfo bufferInfo = { VK_STRUCTURE_TYPE_BUFFER_CREATE_INFO };
bufferInfo.size = 65536;
bufferInfo.usage = VK_BUFFER_USAGE_VERTEX_BUFFER_BIT | VK_BUFFER_USAGE_TRANSFER_DST_BIT;
VmaAllocationCreateInfo allocInfo = {};
allocInfo.usage = VMA_MEMORY_USAGE_GPU_ONLY;
VkBuffer buffer;
VmaAllocation allocation;
vmaCreateBuffer(allocator, &bufferInfo, &allocInfo, &buffer, &allocation, nullptr);
\endcode
Don't forget to destroy your objects when no longer needed:
\code
vmaDestroyBuffer(allocator, buffer, allocation);
vmaDestroyAllocator(allocator);
\endcode
\page choosing_memory_type Choosing memory type
Physical devices in Vulkan support various combinations of memory heaps and
types. Help with choosing correct and optimal memory type for your specific
resource is one of the key features of this library. You can use it by filling
appropriate members of VmaAllocationCreateInfo structure, as described below.
You can also combine multiple methods.
-# If you just want to find memory type index that meets your requirements, you
can use function: vmaFindMemoryTypeIndex(), vmaFindMemoryTypeIndexForBufferInfo(),
vmaFindMemoryTypeIndexForImageInfo().
-# If you want to allocate a region of device memory without association with any
specific image or buffer, you can use function vmaAllocateMemory(). Usage of
this function is not recommended and usually not needed.
vmaAllocateMemoryPages() function is also provided for creating multiple allocations at once,
which may be useful for sparse binding.
-# If you already have a buffer or an image created, you want to allocate memory
for it and then you will bind it yourself, you can use function
vmaAllocateMemoryForBuffer(), vmaAllocateMemoryForImage().
For binding you should use functions: vmaBindBufferMemory(), vmaBindImageMemory().
-# If you want to create a buffer or an image, allocate memory for it and bind
them together, all in one call, you can use function vmaCreateBuffer(),
vmaCreateImage(). This is the easiest and recommended way to use this library.
When using 3. or 4., the library internally queries Vulkan for memory types
supported for that buffer or image (function `vkGetBufferMemoryRequirements()`)
and uses only one of these types.
If no memory type can be found that meets all the requirements, these functions
return `VK_ERROR_FEATURE_NOT_PRESENT`.
You can leave VmaAllocationCreateInfo structure completely filled with zeros.
It means no requirements are specified for memory type.
It is valid, although not very useful.
\section choosing_memory_type_usage Usage
The easiest way to specify memory requirements is to fill member
VmaAllocationCreateInfo::usage using one of the values of enum #VmaMemoryUsage.
It defines high level, common usage types.
For more details, see description of this enum.
For example, if you want to create a uniform buffer that will be filled using
transfer only once or infrequently and used for rendering every frame, you can
do it using following code:
\code
VkBufferCreateInfo bufferInfo = { VK_STRUCTURE_TYPE_BUFFER_CREATE_INFO };
bufferInfo.size = 65536;
bufferInfo.usage = VK_BUFFER_USAGE_UNIFORM_BUFFER_BIT | VK_BUFFER_USAGE_TRANSFER_DST_BIT;
VmaAllocationCreateInfo allocInfo = {};
allocInfo.usage = VMA_MEMORY_USAGE_GPU_ONLY;
VkBuffer buffer;
VmaAllocation allocation;
vmaCreateBuffer(allocator, &bufferInfo, &allocInfo, &buffer, &allocation, nullptr);
\endcode
\section choosing_memory_type_required_preferred_flags Required and preferred flags
You can specify more detailed requirements by filling members
VmaAllocationCreateInfo::requiredFlags and VmaAllocationCreateInfo::preferredFlags
with a combination of bits from enum `VkMemoryPropertyFlags`. For example,
if you want to create a buffer that will be persistently mapped on host (so it
must be `HOST_VISIBLE`) and preferably will also be `HOST_COHERENT` and `HOST_CACHED`,
use following code:
\code
VmaAllocationCreateInfo allocInfo = {};
allocInfo.requiredFlags = VK_MEMORY_PROPERTY_HOST_VISIBLE_BIT;
allocInfo.preferredFlags = VK_MEMORY_PROPERTY_HOST_COHERENT_BIT | VK_MEMORY_PROPERTY_HOST_CACHED_BIT;
allocInfo.flags = VMA_ALLOCATION_CREATE_MAPPED_BIT;
VkBuffer buffer;
VmaAllocation allocation;
vmaCreateBuffer(allocator, &bufferInfo, &allocInfo, &buffer, &allocation, nullptr);
\endcode
A memory type is chosen that has all the required flags and as many preferred
flags set as possible.
If you use VmaAllocationCreateInfo::usage, it is just internally converted to
a set of required and preferred flags.
\section choosing_memory_type_explicit_memory_types Explicit memory types
If you inspected memory types available on the physical device and you have
a preference for memory types that you want to use, you can fill member
VmaAllocationCreateInfo::memoryTypeBits. It is a bit mask, where each bit set
means that a memory type with that index is allowed to be used for the
allocation. Special value 0, just like `UINT32_MAX`, means there are no
restrictions to memory type index.
Please note that this member is NOT just a memory type index.
Still you can use it to choose just one, specific memory type.
For example, if you already determined that your buffer should be created in
memory type 2, use following code:
\code
uint32_t memoryTypeIndex = 2;
VmaAllocationCreateInfo allocInfo = {};
allocInfo.memoryTypeBits = 1u << memoryTypeIndex;
VkBuffer buffer;
VmaAllocation allocation;
vmaCreateBuffer(allocator, &bufferInfo, &allocInfo, &buffer, &allocation, nullptr);
\endcode
\section choosing_memory_type_custom_memory_pools Custom memory pools
If you allocate from custom memory pool, all the ways of specifying memory
requirements described above are not applicable and the aforementioned members
of VmaAllocationCreateInfo structure are ignored. Memory type is selected
explicitly when creating the pool and then used to make all the allocations from
that pool. For further details, see \ref custom_memory_pools.
\section choosing_memory_type_dedicated_allocations Dedicated allocations
Memory for allocations is reserved out of larger block of `VkDeviceMemory`
allocated from Vulkan internally. That's the main feature of this whole library.
You can still request a separate memory block to be created for an allocation,
just like you would do in a trivial solution without using any allocator.
In that case, a buffer or image is always bound to that memory at offset 0.
This is called a "dedicated allocation".
You can explicitly request it by using flag #VMA_ALLOCATION_CREATE_DEDICATED_MEMORY_BIT.
The library can also internally decide to use dedicated allocation in some cases, e.g.:
- When the size of the allocation is large.
- When [VK_KHR_dedicated_allocation](@ref vk_khr_dedicated_allocation) extension is enabled
and it reports that dedicated allocation is required or recommended for the resource.
- When allocation of next big memory block fails due to not enough device memory,
but allocation with the exact requested size succeeds.
\page memory_mapping Memory mapping
To "map memory" in Vulkan means to obtain a CPU pointer to `VkDeviceMemory`,
to be able to read from it or write to it in CPU code.
Mapping is possible only of memory allocated from a memory type that has
`VK_MEMORY_PROPERTY_HOST_VISIBLE_BIT` flag.
Functions `vkMapMemory()`, `vkUnmapMemory()` are designed for this purpose.
You can use them directly with memory allocated by this library,
but it is not recommended because of following issue:
Mapping the same `VkDeviceMemory` block multiple times is illegal - only one mapping at a time is allowed.
This includes mapping disjoint regions. Mapping is not reference-counted internally by Vulkan.
Because of this, Vulkan Memory Allocator provides following facilities:
\section memory_mapping_mapping_functions Mapping functions
The library provides following functions for mapping of a specific #VmaAllocation: vmaMapMemory(), vmaUnmapMemory().
They are safer and more convenient to use than standard Vulkan functions.
You can map an allocation multiple times simultaneously - mapping is reference-counted internally.
You can also map different allocations simultaneously regardless of whether they use the same `VkDeviceMemory` block.
The way it's implemented is that the library always maps entire memory block, not just region of the allocation.
For further details, see description of vmaMapMemory() function.
Example:
\code
// Having these objects initialized:
struct ConstantBuffer
{
...
};
ConstantBuffer constantBufferData;
VmaAllocator allocator;
VkBuffer constantBuffer;
VmaAllocation constantBufferAllocation;
// You can map and fill your buffer using following code:
void* mappedData;
vmaMapMemory(allocator, constantBufferAllocation, &mappedData);
memcpy(mappedData, &constantBufferData, sizeof(constantBufferData));
vmaUnmapMemory(allocator, constantBufferAllocation);
\endcode
When mapping, you may see a warning from Vulkan validation layer similar to this one:
<i>Mapping an image with layout VK_IMAGE_LAYOUT_DEPTH_STENCIL_ATTACHMENT_OPTIMAL can result in undefined behavior if this memory is used by the device. Only GENERAL or PREINITIALIZED should be used.</i>
It happens because the library maps entire `VkDeviceMemory` block, where different
types of images and buffers may end up together, especially on GPUs with unified memory like Intel.
You can safely ignore it if you are sure you access only memory of the intended
object that you wanted to map.
\section memory_mapping_persistently_mapped_memory Persistently mapped memory
Kepping your memory persistently mapped is generally OK in Vulkan.
You don't need to unmap it before using its data on the GPU.
The library provides a special feature designed for that:
Allocations made with #VMA_ALLOCATION_CREATE_MAPPED_BIT flag set in
VmaAllocationCreateInfo::flags stay mapped all the time,
so you can just access CPU pointer to it any time
without a need to call any "map" or "unmap" function.
Example:
\code
VkBufferCreateInfo bufCreateInfo = { VK_STRUCTURE_TYPE_BUFFER_CREATE_INFO };
bufCreateInfo.size = sizeof(ConstantBuffer);
bufCreateInfo.usage = VK_BUFFER_USAGE_TRANSFER_SRC_BIT;
VmaAllocationCreateInfo allocCreateInfo = {};
allocCreateInfo.usage = VMA_MEMORY_USAGE_CPU_ONLY;
allocCreateInfo.flags = VMA_ALLOCATION_CREATE_MAPPED_BIT;
VkBuffer buf;
VmaAllocation alloc;
VmaAllocationInfo allocInfo;
vmaCreateBuffer(allocator, &bufCreateInfo, &allocCreateInfo, &buf, &alloc, &allocInfo);
// Buffer is already mapped. You can access its memory.
memcpy(allocInfo.pMappedData, &constantBufferData, sizeof(constantBufferData));
\endcode
There are some exceptions though, when you should consider mapping memory only for a short period of time:
- When operating system is Windows 7 or 8.x (Windows 10 is not affected because it uses WDDM2),
device is discrete AMD GPU,
and memory type is the special 256 MiB pool of `DEVICE_LOCAL + HOST_VISIBLE` memory
(selected when you use #VMA_MEMORY_USAGE_CPU_TO_GPU),
then whenever a memory block allocated from this memory type stays mapped
for the time of any call to `vkQueueSubmit()` or `vkQueuePresentKHR()`, this
block is migrated by WDDM to system RAM, which degrades performance. It doesn't
matter if that particular memory block is actually used by the command buffer
being submitted.
- On Mac/MoltenVK there is a known bug - [Issue #175](https://github.com/KhronosGroup/MoltenVK/issues/175)
which requires unmapping before GPU can see updated texture.
- Keeping many large memory blocks mapped may impact performance or stability of some debugging tools.
\section memory_mapping_cache_control Cache control
Memory in Vulkan doesn't need to be unmapped before using it on GPU,
but unless a memory types has `VK_MEMORY_PROPERTY_HOST_COHERENT_BIT` flag set,
you need to manually invalidate cache before reading of mapped pointer
and flush cache after writing to mapped pointer.
Vulkan provides following functions for this purpose `vkFlushMappedMemoryRanges()`,
`vkInvalidateMappedMemoryRanges()`, but this library provides more convenient
functions that refer to given allocation object: vmaFlushAllocation(),
vmaInvalidateAllocation().
Regions of memory specified for flush/invalidate must be aligned to
`VkPhysicalDeviceLimits::nonCoherentAtomSize`. This is automatically ensured by the library.
In any memory type that is `HOST_VISIBLE` but not `HOST_COHERENT`, all allocations
within blocks are aligned to this value, so their offsets are always multiply of
`nonCoherentAtomSize` and two different allocations never share same "line" of this size.
Please note that memory allocated with #VMA_MEMORY_USAGE_CPU_ONLY is guaranteed to be `HOST_COHERENT`.
Also, Windows drivers from all 3 PC GPU vendors (AMD, Intel, NVIDIA)
currently provide `HOST_COHERENT` flag on all memory types that are
`HOST_VISIBLE`, so on this platform you may not need to bother.
\section memory_mapping_finding_if_memory_mappable Finding out if memory is mappable
It may happen that your allocation ends up in memory that is `HOST_VISIBLE` (available for mapping)
despite it wasn't explicitly requested.
For example, application may work on integrated graphics with unified memory (like Intel) or
allocation from video memory might have failed, so the library chose system memory as fallback.
You can detect this case and map such allocation to access its memory on CPU directly,
instead of launching a transfer operation.
In order to do that: inspect `allocInfo.memoryType`, call vmaGetMemoryTypeProperties(),
and look for `VK_MEMORY_PROPERTY_HOST_VISIBLE_BIT` flag in properties of that memory type.
\code
VkBufferCreateInfo bufCreateInfo = { VK_STRUCTURE_TYPE_BUFFER_CREATE_INFO };
bufCreateInfo.size = sizeof(ConstantBuffer);
bufCreateInfo.usage = VK_BUFFER_USAGE_UNIFORM_BUFFER_BIT | VK_BUFFER_USAGE_TRANSFER_DST_BIT;
VmaAllocationCreateInfo allocCreateInfo = {};
allocCreateInfo.usage = VMA_MEMORY_USAGE_GPU_ONLY;
allocCreateInfo.preferredFlags = VK_MEMORY_PROPERTY_HOST_VISIBLE_BIT;
VkBuffer buf;
VmaAllocation alloc;
VmaAllocationInfo allocInfo;
vmaCreateBuffer(allocator, &bufCreateInfo, &allocCreateInfo, &buf, &alloc, &allocInfo);
VkMemoryPropertyFlags memFlags;
vmaGetMemoryTypeProperties(allocator, allocInfo.memoryType, &memFlags);
if((memFlags & VK_MEMORY_PROPERTY_HOST_VISIBLE_BIT) == 0)
{
// Allocation ended up in mappable memory. You can map it and access it directly.
void* mappedData;
vmaMapMemory(allocator, alloc, &mappedData);
memcpy(mappedData, &constantBufferData, sizeof(constantBufferData));
vmaUnmapMemory(allocator, alloc);
}
else
{
// Allocation ended up in non-mappable memory.
// You need to create CPU-side buffer in VMA_MEMORY_USAGE_CPU_ONLY and make a transfer.
}
\endcode
You can even use #VMA_ALLOCATION_CREATE_MAPPED_BIT flag while creating allocations
that are not necessarily `HOST_VISIBLE` (e.g. using #VMA_MEMORY_USAGE_GPU_ONLY).
If the allocation ends up in memory type that is `HOST_VISIBLE`, it will be persistently mapped and you can use it directly.
If not, the flag is just ignored.
Example:
\code
VkBufferCreateInfo bufCreateInfo = { VK_STRUCTURE_TYPE_BUFFER_CREATE_INFO };
bufCreateInfo.size = sizeof(ConstantBuffer);
bufCreateInfo.usage = VK_BUFFER_USAGE_UNIFORM_BUFFER_BIT | VK_BUFFER_USAGE_TRANSFER_DST_BIT;
VmaAllocationCreateInfo allocCreateInfo = {};
allocCreateInfo.usage = VMA_MEMORY_USAGE_GPU_ONLY;
allocCreateInfo.flags = VMA_ALLOCATION_CREATE_MAPPED_BIT;
VkBuffer buf;
VmaAllocation alloc;
VmaAllocationInfo allocInfo;
vmaCreateBuffer(allocator, &bufCreateInfo, &allocCreateInfo, &buf, &alloc, &allocInfo);
if(allocInfo.pUserData != nullptr)
{
// Allocation ended up in mappable memory.
// It's persistently mapped. You can access it directly.
memcpy(allocInfo.pMappedData, &constantBufferData, sizeof(constantBufferData));
}
else
{
// Allocation ended up in non-mappable memory.
// You need to create CPU-side buffer in VMA_MEMORY_USAGE_CPU_ONLY and make a transfer.
}
\endcode
\page custom_memory_pools Custom memory pools
A memory pool contains a number of `VkDeviceMemory` blocks.
The library automatically creates and manages default pool for each memory type available on the device.
Default memory pool automatically grows in size.
Size of allocated blocks is also variable and managed automatically.
You can create custom pool and allocate memory out of it.
It can be useful if you want to:
- Keep certain kind of allocations separate from others.
- Enforce particular, fixed size of Vulkan memory blocks.
- Limit maximum amount of Vulkan memory allocated for that pool.
- Reserve minimum or fixed amount of Vulkan memory always preallocated for that pool.
To use custom memory pools:
-# Fill VmaPoolCreateInfo structure.
-# Call vmaCreatePool() to obtain #VmaPool handle.
-# When making an allocation, set VmaAllocationCreateInfo::pool to this handle.
You don't need to specify any other parameters of this structure, like `usage`.
Example:
\code
// Create a pool that can have at most 2 blocks, 128 MiB each.
VmaPoolCreateInfo poolCreateInfo = {};
poolCreateInfo.memoryTypeIndex = ...
poolCreateInfo.blockSize = 128ull * 1024 * 1024;
poolCreateInfo.maxBlockCount = 2;
VmaPool pool;
vmaCreatePool(allocator, &poolCreateInfo, &pool);
// Allocate a buffer out of it.
VkBufferCreateInfo bufCreateInfo = { VK_STRUCTURE_TYPE_BUFFER_CREATE_INFO };
bufCreateInfo.size = 1024;
bufCreateInfo.usage = VK_BUFFER_USAGE_UNIFORM_BUFFER_BIT | VK_BUFFER_USAGE_TRANSFER_DST_BIT;
VmaAllocationCreateInfo allocCreateInfo = {};
allocCreateInfo.pool = pool;
VkBuffer buf;
VmaAllocation alloc;
VmaAllocationInfo allocInfo;
vmaCreateBuffer(allocator, &bufCreateInfo, &allocCreateInfo, &buf, &alloc, &allocInfo);
\endcode
You have to free all allocations made from this pool before destroying it.
\code
vmaDestroyBuffer(allocator, buf, alloc);
vmaDestroyPool(allocator, pool);
\endcode
\section custom_memory_pools_MemTypeIndex Choosing memory type index
When creating a pool, you must explicitly specify memory type index.
To find the one suitable for your buffers or images, you can use helper functions
vmaFindMemoryTypeIndexForBufferInfo(), vmaFindMemoryTypeIndexForImageInfo().
You need to provide structures with example parameters of buffers or images
that you are going to create in that pool.
\code
VkBufferCreateInfo exampleBufCreateInfo = { VK_STRUCTURE_TYPE_BUFFER_CREATE_INFO };
exampleBufCreateInfo.size = 1024; // Whatever.
exampleBufCreateInfo.usage = VK_BUFFER_USAGE_UNIFORM_BUFFER_BIT | VK_BUFFER_USAGE_TRANSFER_DST_BIT; // Change if needed.
VmaAllocationCreateInfo allocCreateInfo = {};
allocCreateInfo.usage = VMA_MEMORY_USAGE_GPU_ONLY; // Change if needed.
uint32_t memTypeIndex;
vmaFindMemoryTypeIndexForBufferInfo(allocator, &exampleBufCreateInfo, &allocCreateInfo, &memTypeIndex);
VmaPoolCreateInfo poolCreateInfo = {};
poolCreateInfo.memoryTypeIndex = memTypeIndex;
// ...
\endcode
When creating buffers/images allocated in that pool, provide following parameters:
- `VkBufferCreateInfo`: Prefer to pass same parameters as above.
Otherwise you risk creating resources in a memory type that is not suitable for them, which may result in undefined behavior.
Using different `VK_BUFFER_USAGE_` flags may work, but you shouldn't create images in a pool intended for buffers
or the other way around.
- VmaAllocationCreateInfo: You don't need to pass same parameters. Fill only `pool` member.
Other members are ignored anyway.
\section linear_algorithm Linear allocation algorithm
Each Vulkan memory block managed by this library has accompanying metadata that
keeps track of used and unused regions. By default, the metadata structure and
algorithm tries to find best place for new allocations among free regions to
optimize memory usage. This way you can allocate and free objects in any order.
![Default allocation algorithm](../gfx/Linear_allocator_1_algo_default.png)
Sometimes there is a need to use simpler, linear allocation algorithm. You can
create custom pool that uses such algorithm by adding flag
#VMA_POOL_CREATE_LINEAR_ALGORITHM_BIT to VmaPoolCreateInfo::flags while creating
#VmaPool object. Then an alternative metadata management is used. It always
creates new allocations after last one and doesn't reuse free regions after
allocations freed in the middle. It results in better allocation performance and
less memory consumed by metadata.
![Linear allocation algorithm](../gfx/Linear_allocator_2_algo_linear.png)
With this one flag, you can create a custom pool that can be used in many ways:
free-at-once, stack, double stack, and ring buffer. See below for details.
\subsection linear_algorithm_free_at_once Free-at-once
In a pool that uses linear algorithm, you still need to free all the allocations
individually, e.g. by using vmaFreeMemory() or vmaDestroyBuffer(). You can free
them in any order. New allocations are always made after last one - free space
in the middle is not reused. However, when you release all the allocation and
the pool becomes empty, allocation starts from the beginning again. This way you
can use linear algorithm to speed up creation of allocations that you are going
to release all at once.
![Free-at-once](../gfx/Linear_allocator_3_free_at_once.png)
This mode is also available for pools created with VmaPoolCreateInfo::maxBlockCount
value that allows multiple memory blocks.
\subsection linear_algorithm_stack Stack
When you free an allocation that was created last, its space can be reused.
Thanks to this, if you always release allocations in the order opposite to their
creation (LIFO - Last In First Out), you can achieve behavior of a stack.
![Stack](../gfx/Linear_allocator_4_stack.png)
This mode is also available for pools created with VmaPoolCreateInfo::maxBlockCount
value that allows multiple memory blocks.
\subsection linear_algorithm_double_stack Double stack
The space reserved by a custom pool with linear algorithm may be used by two
stacks:
- First, default one, growing up from offset 0.
- Second, "upper" one, growing down from the end towards lower offsets.
To make allocation from upper stack, add flag #VMA_ALLOCATION_CREATE_UPPER_ADDRESS_BIT
to VmaAllocationCreateInfo::flags.
![Double stack](../gfx/Linear_allocator_7_double_stack.png)
Double stack is available only in pools with one memory block -
VmaPoolCreateInfo::maxBlockCount must be 1. Otherwise behavior is undefined.
When the two stacks' ends meet so there is not enough space between them for a
new allocation, such allocation fails with usual
`VK_ERROR_OUT_OF_DEVICE_MEMORY` error.
\subsection linear_algorithm_ring_buffer Ring buffer
When you free some allocations from the beginning and there is not enough free space
for a new one at the end of a pool, allocator's "cursor" wraps around to the
beginning and starts allocation there. Thanks to this, if you always release
allocations in the same order as you created them (FIFO - First In First Out),
you can achieve behavior of a ring buffer / queue.
![Ring buffer](../gfx/Linear_allocator_5_ring_buffer.png)
Pools with linear algorithm support [lost allocations](@ref lost_allocations) when used as ring buffer.
If there is not enough free space for a new allocation, but existing allocations
from the front of the queue can become lost, they become lost and the allocation
succeeds.
![Ring buffer with lost allocations](../gfx/Linear_allocator_6_ring_buffer_lost.png)
Ring buffer is available only in pools with one memory block -
VmaPoolCreateInfo::maxBlockCount must be 1. Otherwise behavior is undefined.
\section buddy_algorithm Buddy allocation algorithm
There is another allocation algorithm that can be used with custom pools, called
"buddy". Its internal data structure is based on a tree of blocks, each having
size that is a power of two and a half of its parent's size. When you want to
allocate memory of certain size, a free node in the tree is located. If it's too
large, it is recursively split into two halves (called "buddies"). However, if
requested allocation size is not a power of two, the size of a tree node is
aligned up to the nearest power of two and the remaining space is wasted. When
two buddy nodes become free, they are merged back into one larger node.
![Buddy allocator](../gfx/Buddy_allocator.png)
The advantage of buddy allocation algorithm over default algorithm is faster
allocation and deallocation, as well as smaller external fragmentation. The
disadvantage is more wasted space (internal fragmentation).
For more information, please read ["Buddy memory allocation" on Wikipedia](https://en.wikipedia.org/wiki/Buddy_memory_allocation)
or other sources that describe this concept in general.
To use buddy allocation algorithm with a custom pool, add flag
#VMA_POOL_CREATE_BUDDY_ALGORITHM_BIT to VmaPoolCreateInfo::flags while creating
#VmaPool object.
Several limitations apply to pools that use buddy algorithm:
- It is recommended to use VmaPoolCreateInfo::blockSize that is a power of two.
Otherwise, only largest power of two smaller than the size is used for
allocations. The remaining space always stays unused.
- [Margins](@ref debugging_memory_usage_margins) and
[corruption detection](@ref debugging_memory_usage_corruption_detection)
don't work in such pools.
- [Lost allocations](@ref lost_allocations) don't work in such pools. You can
use them, but they never become lost. Support may be added in the future.
- [Defragmentation](@ref defragmentation) doesn't work with allocations made from
such pool.
\page defragmentation Defragmentation
Interleaved allocations and deallocations of many objects of varying size can
cause fragmentation over time, which can lead to a situation where the library is unable
to find a continuous range of free memory for a new allocation despite there is
enough free space, just scattered across many small free ranges between existing
allocations.
To mitigate this problem, you can use defragmentation feature:
structure #VmaDefragmentationInfo2, function vmaDefragmentationBegin(), vmaDefragmentationEnd().
Given set of allocations,
this function can move them to compact used memory, ensure more continuous free
space and possibly also free some `VkDeviceMemory` blocks.
What the defragmentation does is:
- Updates #VmaAllocation objects to point to new `VkDeviceMemory` and offset.
After allocation has been moved, its VmaAllocationInfo::deviceMemory and/or
VmaAllocationInfo::offset changes. You must query them again using
vmaGetAllocationInfo() if you need them.
- Moves actual data in memory.
What it doesn't do, so you need to do it yourself:
- Recreate buffers and images that were bound to allocations that were defragmented and
bind them with their new places in memory.
You must use `vkDestroyBuffer()`, `vkDestroyImage()`,
`vkCreateBuffer()`, `vkCreateImage()` for that purpose and NOT vmaDestroyBuffer(),
vmaDestroyImage(), vmaCreateBuffer(), vmaCreateImage(), because you don't need to
destroy or create allocation objects!
- Recreate views and update descriptors that point to these buffers and images.
\section defragmentation_cpu Defragmenting CPU memory
Following example demonstrates how you can run defragmentation on CPU.
Only allocations created in memory types that are `HOST_VISIBLE` can be defragmented.
Others are ignored.
The way it works is:
- It temporarily maps entire memory blocks when necessary.
- It moves data using `memmove()` function.
\code
// Given following variables already initialized:
VkDevice device;
VmaAllocator allocator;
std::vector<VkBuffer> buffers;
std::vector<VmaAllocation> allocations;
const uint32_t allocCount = (uint32_t)allocations.size();
std::vector<VkBool32> allocationsChanged(allocCount);
VmaDefragmentationInfo2 defragInfo = {};
defragInfo.allocationCount = allocCount;
defragInfo.pAllocations = allocations.data();
defragInfo.pAllocationsChanged = allocationsChanged.data();
defragInfo.maxCpuBytesToMove = VK_WHOLE_SIZE; // No limit.
defragInfo.maxCpuAllocationsToMove = UINT32_MAX; // No limit.
VmaDefragmentationContext defragCtx;
vmaDefragmentationBegin(allocator, &defragInfo, nullptr, &defragCtx);
vmaDefragmentationEnd(allocator, defragCtx);
for(uint32_t i = 0; i < allocCount; ++i)
{
if(allocationsChanged[i])
{
// Destroy buffer that is immutably bound to memory region which is no longer valid.
vkDestroyBuffer(device, buffers[i], nullptr);
// Create new buffer with same parameters.
VkBufferCreateInfo bufferInfo = ...;
vkCreateBuffer(device, &bufferInfo, nullptr, &buffers[i]);
// You can make dummy call to vkGetBufferMemoryRequirements here to silence validation layer warning.
// Bind new buffer to new memory region. Data contained in it is already moved.
VmaAllocationInfo allocInfo;
vmaGetAllocationInfo(allocator, allocations[i], &allocInfo);
vkBindBufferMemory(device, buffers[i], allocInfo.deviceMemory, allocInfo.offset);
}
}
\endcode
Setting VmaDefragmentationInfo2::pAllocationsChanged is optional.
This output array tells whether particular allocation in VmaDefragmentationInfo2::pAllocations at the same index
has been modified during defragmentation.
You can pass null, but you then need to query every allocation passed to defragmentation
for new parameters using vmaGetAllocationInfo() if you might need to recreate and rebind a buffer or image associated with it.
If you use [Custom memory pools](@ref choosing_memory_type_custom_memory_pools),
you can fill VmaDefragmentationInfo2::poolCount and VmaDefragmentationInfo2::pPools
instead of VmaDefragmentationInfo2::allocationCount and VmaDefragmentationInfo2::pAllocations
to defragment all allocations in given pools.
You cannot use VmaDefragmentationInfo2::pAllocationsChanged in that case.
You can also combine both methods.
\section defragmentation_gpu Defragmenting GPU memory
It is also possible to defragment allocations created in memory types that are not `HOST_VISIBLE`.
To do that, you need to pass a command buffer that meets requirements as described in
VmaDefragmentationInfo2::commandBuffer. The way it works is:
- It creates temporary buffers and binds them to entire memory blocks when necessary.
- It issues `vkCmdCopyBuffer()` to passed command buffer.
Example:
\code
// Given following variables already initialized:
VkDevice device;
VmaAllocator allocator;
VkCommandBuffer commandBuffer;
std::vector<VkBuffer> buffers;
std::vector<VmaAllocation> allocations;
const uint32_t allocCount = (uint32_t)allocations.size();
std::vector<VkBool32> allocationsChanged(allocCount);
VkCommandBufferBeginInfo cmdBufBeginInfo = ...;
vkBeginCommandBuffer(commandBuffer, &cmdBufBeginInfo);
VmaDefragmentationInfo2 defragInfo = {};
defragInfo.allocationCount = allocCount;
defragInfo.pAllocations = allocations.data();
defragInfo.pAllocationsChanged = allocationsChanged.data();
defragInfo.maxGpuBytesToMove = VK_WHOLE_SIZE; // Notice it's "GPU" this time.
defragInfo.maxGpuAllocationsToMove = UINT32_MAX; // Notice it's "GPU" this time.
defragInfo.commandBuffer = commandBuffer;
VmaDefragmentationContext defragCtx;
vmaDefragmentationBegin(allocator, &defragInfo, nullptr, &defragCtx);
vkEndCommandBuffer(commandBuffer);
// Submit commandBuffer.
// Wait for a fence that ensures commandBuffer execution finished.
vmaDefragmentationEnd(allocator, defragCtx);
for(uint32_t i = 0; i < allocCount; ++i)
{
if(allocationsChanged[i])
{
// Destroy buffer that is immutably bound to memory region which is no longer valid.
vkDestroyBuffer(device, buffers[i], nullptr);
// Create new buffer with same parameters.
VkBufferCreateInfo bufferInfo = ...;
vkCreateBuffer(device, &bufferInfo, nullptr, &buffers[i]);
// You can make dummy call to vkGetBufferMemoryRequirements here to silence validation layer warning.
// Bind new buffer to new memory region. Data contained in it is already moved.
VmaAllocationInfo allocInfo;
vmaGetAllocationInfo(allocator, allocations[i], &allocInfo);
vkBindBufferMemory(device, buffers[i], allocInfo.deviceMemory, allocInfo.offset);
}
}
\endcode
You can combine these two methods by specifying non-zero `maxGpu*` as well as `maxCpu*` parameters.
The library automatically chooses best method to defragment each memory pool.
You may try not to block your entire program to wait until defragmentation finishes,
but do it in the background, as long as you carefully fullfill requirements described
in function vmaDefragmentationBegin().
\section defragmentation_additional_notes Additional notes
It is only legal to defragment allocations bound to:
- buffers
- images created with `VK_IMAGE_CREATE_ALIAS_BIT`, `VK_IMAGE_TILING_LINEAR`, and
being currently in `VK_IMAGE_LAYOUT_GENERAL` or `VK_IMAGE_LAYOUT_PREINITIALIZED`.
Defragmentation of images created with `VK_IMAGE_TILING_OPTIMAL` or in any other
layout may give undefined results.
If you defragment allocations bound to images, new images to be bound to new
memory region after defragmentation should be created with `VK_IMAGE_LAYOUT_PREINITIALIZED`
and then transitioned to their original layout from before defragmentation if
needed using an image memory barrier.
While using defragmentation, you may experience validation layer warnings, which you just need to ignore.
See [Validation layer warnings](@ref general_considerations_validation_layer_warnings).
Please don't expect memory to be fully compacted after defragmentation.
Algorithms inside are based on some heuristics that try to maximize number of Vulkan
memory blocks to make totally empty to release them, as well as to maximimze continuous
empty space inside remaining blocks, while minimizing the number and size of allocations that
need to be moved. Some fragmentation may still remain - this is normal.
\section defragmentation_custom_algorithm Writing custom defragmentation algorithm
If you want to implement your own, custom defragmentation algorithm,
there is infrastructure prepared for that,
but it is not exposed through the library API - you need to hack its source code.
Here are steps needed to do this:
-# Main thing you need to do is to define your own class derived from base abstract
class `VmaDefragmentationAlgorithm` and implement your version of its pure virtual methods.
See definition and comments of this class for details.
-# Your code needs to interact with device memory block metadata.
If you need more access to its data than it's provided by its public interface,
declare your new class as a friend class e.g. in class `VmaBlockMetadata_Generic`.
-# If you want to create a flag that would enable your algorithm or pass some additional
flags to configure it, add them to `VmaDefragmentationFlagBits` and use them in
VmaDefragmentationInfo2::flags.
-# Modify function `VmaBlockVectorDefragmentationContext::Begin` to create object
of your new class whenever needed.
\page lost_allocations Lost allocations
If your game oversubscribes video memory, if may work OK in previous-generation
graphics APIs (DirectX 9, 10, 11, OpenGL) because resources are automatically
paged to system RAM. In Vulkan you can't do it because when you run out of
memory, an allocation just fails. If you have more data (e.g. textures) that can
fit into VRAM and you don't need it all at once, you may want to upload them to
GPU on demand and "push out" ones that are not used for a long time to make room
for the new ones, effectively using VRAM (or a cartain memory pool) as a form of
cache. Vulkan Memory Allocator can help you with that by supporting a concept of
"lost allocations".
To create an allocation that can become lost, include #VMA_ALLOCATION_CREATE_CAN_BECOME_LOST_BIT
flag in VmaAllocationCreateInfo::flags. Before using a buffer or image bound to
such allocation in every new frame, you need to query it if it's not lost.
To check it, call vmaTouchAllocation().
If the allocation is lost, you should not use it or buffer/image bound to it.
You mustn't forget to destroy this allocation and this buffer/image.
vmaGetAllocationInfo() can also be used for checking status of the allocation.
Allocation is lost when returned VmaAllocationInfo::deviceMemory == `VK_NULL_HANDLE`.
To create an allocation that can make some other allocations lost to make room
for it, use #VMA_ALLOCATION_CREATE_CAN_MAKE_OTHER_LOST_BIT flag. You will
usually use both flags #VMA_ALLOCATION_CREATE_CAN_MAKE_OTHER_LOST_BIT and
#VMA_ALLOCATION_CREATE_CAN_BECOME_LOST_BIT at the same time.
Warning! Current implementation uses quite naive, brute force algorithm,
which can make allocation calls that use #VMA_ALLOCATION_CREATE_CAN_MAKE_OTHER_LOST_BIT
flag quite slow. A new, more optimal algorithm and data structure to speed this
up is planned for the future.
<b>Q: When interleaving creation of new allocations with usage of existing ones,
how do you make sure that an allocation won't become lost while it's used in the
current frame?</b>
It is ensured because vmaTouchAllocation() / vmaGetAllocationInfo() not only returns allocation
status/parameters and checks whether it's not lost, but when it's not, it also
atomically marks it as used in the current frame, which makes it impossible to
become lost in that frame. It uses lockless algorithm, so it works fast and
doesn't involve locking any internal mutex.
<b>Q: What if my allocation may still be in use by the GPU when it's rendering a
previous frame while I already submit new frame on the CPU?</b>
You can make sure that allocations "touched" by vmaTouchAllocation() / vmaGetAllocationInfo() will not
become lost for a number of additional frames back from the current one by
specifying this number as VmaAllocatorCreateInfo::frameInUseCount (for default
memory pool) and VmaPoolCreateInfo::frameInUseCount (for custom pool).
<b>Q: How do you inform the library when new frame starts?</b>
You need to call function vmaSetCurrentFrameIndex().
Example code:
\code
struct MyBuffer
{
VkBuffer m_Buf = nullptr;
VmaAllocation m_Alloc = nullptr;
// Called when the buffer is really needed in the current frame.
void EnsureBuffer();
};
void MyBuffer::EnsureBuffer()
{
// Buffer has been created.
if(m_Buf != VK_NULL_HANDLE)
{
// Check if its allocation is not lost + mark it as used in current frame.
if(vmaTouchAllocation(allocator, m_Alloc))
{
// It's all OK - safe to use m_Buf.
return;
}
}
// Buffer not yet exists or lost - destroy and recreate it.
vmaDestroyBuffer(allocator, m_Buf, m_Alloc);
VkBufferCreateInfo bufCreateInfo = { VK_STRUCTURE_TYPE_BUFFER_CREATE_INFO };
bufCreateInfo.size = 1024;
bufCreateInfo.usage = VK_BUFFER_USAGE_UNIFORM_BUFFER_BIT | VK_BUFFER_USAGE_TRANSFER_DST_BIT;
VmaAllocationCreateInfo allocCreateInfo = {};
allocCreateInfo.usage = VMA_MEMORY_USAGE_GPU_ONLY;
allocCreateInfo.flags = VMA_ALLOCATION_CREATE_CAN_BECOME_LOST_BIT |
VMA_ALLOCATION_CREATE_CAN_MAKE_OTHER_LOST_BIT;
vmaCreateBuffer(allocator, &bufCreateInfo, &allocCreateInfo, &m_Buf, &m_Alloc, nullptr);
}
\endcode
When using lost allocations, you may see some Vulkan validation layer warnings
about overlapping regions of memory bound to different kinds of buffers and
images. This is still valid as long as you implement proper handling of lost
allocations (like in the example above) and don't use them.
You can create an allocation that is already in lost state from the beginning using function
vmaCreateLostAllocation(). It may be useful if you need a "dummy" allocation that is not null.
You can call function vmaMakePoolAllocationsLost() to set all eligible allocations
in a specified custom pool to lost state.
Allocations that have been "touched" in current frame or VmaPoolCreateInfo::frameInUseCount frames back
cannot become lost.
<b>Q: Can I touch allocation that cannot become lost?</b>
Yes, although it has no visible effect.
Calls to vmaGetAllocationInfo() and vmaTouchAllocation() update last use frame index
also for allocations that cannot become lost, but the only way to observe it is to dump
internal allocator state using vmaBuildStatsString().
You can use this feature for debugging purposes to explicitly mark allocations that you use
in current frame and then analyze JSON dump to see for how long each allocation stays unused.
\page statistics Statistics
This library contains functions that return information about its internal state,
especially the amount of memory allocated from Vulkan.
Please keep in mind that these functions need to traverse all internal data structures
to gather these information, so they may be quite time-consuming.
Don't call them too often.
\section statistics_numeric_statistics Numeric statistics
You can query for overall statistics of the allocator using function vmaCalculateStats().
Information are returned using structure #VmaStats.
It contains #VmaStatInfo - number of allocated blocks, number of allocations
(occupied ranges in these blocks), number of unused (free) ranges in these blocks,
number of bytes used and unused (but still allocated from Vulkan) and other information.
They are summed across memory heaps, memory types and total for whole allocator.
You can query for statistics of a custom pool using function vmaGetPoolStats().
Information are returned using structure #VmaPoolStats.
You can query for information about specific allocation using function vmaGetAllocationInfo().
It fill structure #VmaAllocationInfo.
\section statistics_json_dump JSON dump
You can dump internal state of the allocator to a string in JSON format using function vmaBuildStatsString().
The result is guaranteed to be correct JSON.
It uses ANSI encoding.
Any strings provided by user (see [Allocation names](@ref allocation_names))
are copied as-is and properly escaped for JSON, so if they use UTF-8, ISO-8859-2 or any other encoding,
this JSON string can be treated as using this encoding.
It must be freed using function vmaFreeStatsString().
The format of this JSON string is not part of official documentation of the library,
but it will not change in backward-incompatible way without increasing library major version number
and appropriate mention in changelog.
The JSON string contains all the data that can be obtained using vmaCalculateStats().
It can also contain detailed map of allocated memory blocks and their regions -
free and occupied by allocations.
This allows e.g. to visualize the memory or assess fragmentation.
\page allocation_annotation Allocation names and user data
\section allocation_user_data Allocation user data
You can annotate allocations with your own information, e.g. for debugging purposes.
To do that, fill VmaAllocationCreateInfo::pUserData field when creating
an allocation. It's an opaque `void*` pointer. You can use it e.g. as a pointer,
some handle, index, key, ordinal number or any other value that would associate
the allocation with your custom metadata.
\code
VkBufferCreateInfo bufferInfo = { VK_STRUCTURE_TYPE_BUFFER_CREATE_INFO };
// Fill bufferInfo...
MyBufferMetadata* pMetadata = CreateBufferMetadata();
VmaAllocationCreateInfo allocCreateInfo = {};
allocCreateInfo.usage = VMA_MEMORY_USAGE_GPU_ONLY;
allocCreateInfo.pUserData = pMetadata;
VkBuffer buffer;
VmaAllocation allocation;
vmaCreateBuffer(allocator, &bufferInfo, &allocCreateInfo, &buffer, &allocation, nullptr);
\endcode
The pointer may be later retrieved as VmaAllocationInfo::pUserData:
\code
VmaAllocationInfo allocInfo;
vmaGetAllocationInfo(allocator, allocation, &allocInfo);
MyBufferMetadata* pMetadata = (MyBufferMetadata*)allocInfo.pUserData;
\endcode
It can also be changed using function vmaSetAllocationUserData().
Values of (non-zero) allocations' `pUserData` are printed in JSON report created by
vmaBuildStatsString(), in hexadecimal form.
\section allocation_names Allocation names
There is alternative mode available where `pUserData` pointer is used to point to
a null-terminated string, giving a name to the allocation. To use this mode,
set #VMA_ALLOCATION_CREATE_USER_DATA_COPY_STRING_BIT flag in VmaAllocationCreateInfo::flags.
Then `pUserData` passed as VmaAllocationCreateInfo::pUserData or argument to
vmaSetAllocationUserData() must be either null or pointer to a null-terminated string.
The library creates internal copy of the string, so the pointer you pass doesn't need
to be valid for whole lifetime of the allocation. You can free it after the call.
\code
VkImageCreateInfo imageInfo = { VK_STRUCTURE_TYPE_IMAGE_CREATE_INFO };
// Fill imageInfo...
std::string imageName = "Texture: ";
imageName += fileName;
VmaAllocationCreateInfo allocCreateInfo = {};
allocCreateInfo.usage = VMA_MEMORY_USAGE_GPU_ONLY;
allocCreateInfo.flags = VMA_ALLOCATION_CREATE_USER_DATA_COPY_STRING_BIT;
allocCreateInfo.pUserData = imageName.c_str();
VkImage image;
VmaAllocation allocation;
vmaCreateImage(allocator, &imageInfo, &allocCreateInfo, &image, &allocation, nullptr);
\endcode
The value of `pUserData` pointer of the allocation will be different than the one
you passed when setting allocation's name - pointing to a buffer managed
internally that holds copy of the string.
\code
VmaAllocationInfo allocInfo;
vmaGetAllocationInfo(allocator, allocation, &allocInfo);
const char* imageName = (const char*)allocInfo.pUserData;
printf("Image name: %s\n", imageName);
\endcode
That string is also printed in JSON report created by vmaBuildStatsString().
\page debugging_memory_usage Debugging incorrect memory usage
If you suspect a bug with memory usage, like usage of uninitialized memory or
memory being overwritten out of bounds of an allocation,
you can use debug features of this library to verify this.
\section debugging_memory_usage_initialization Memory initialization
If you experience a bug with incorrect and nondeterministic data in your program and you suspect uninitialized memory to be used,
you can enable automatic memory initialization to verify this.
To do it, define macro `VMA_DEBUG_INITIALIZE_ALLOCATIONS` to 1.
\code
#define VMA_DEBUG_INITIALIZE_ALLOCATIONS 1
#include "vk_mem_alloc.h"
\endcode
It makes memory of all new allocations initialized to bit pattern `0xDCDCDCDC`.
Before an allocation is destroyed, its memory is filled with bit pattern `0xEFEFEFEF`.
Memory is automatically mapped and unmapped if necessary.
If you find these values while debugging your program, good chances are that you incorrectly
read Vulkan memory that is allocated but not initialized, or already freed, respectively.
Memory initialization works only with memory types that are `HOST_VISIBLE`.
It works also with dedicated allocations.
It doesn't work with allocations created with #VMA_ALLOCATION_CREATE_CAN_BECOME_LOST_BIT flag,
as they cannot be mapped.
\section debugging_memory_usage_margins Margins
By default, allocations are laid out in memory blocks next to each other if possible
(considering required alignment, `bufferImageGranularity`, and `nonCoherentAtomSize`).
![Allocations without margin](../gfx/Margins_1.png)
Define macro `VMA_DEBUG_MARGIN` to some non-zero value (e.g. 16) to enforce specified
number of bytes as a margin before and after every allocation.
\code
#define VMA_DEBUG_MARGIN 16
#include "vk_mem_alloc.h"
\endcode
![Allocations with margin](../gfx/Margins_2.png)
If your bug goes away after enabling margins, it means it may be caused by memory
being overwritten outside of allocation boundaries. It is not 100% certain though.
Change in application behavior may also be caused by different order and distribution
of allocations across memory blocks after margins are applied.
The margin is applied also before first and after last allocation in a block.
It may occur only once between two adjacent allocations.
Margins work with all types of memory.
Margin is applied only to allocations made out of memory blocks and not to dedicated
allocations, which have their own memory block of specific size.
It is thus not applied to allocations made using #VMA_ALLOCATION_CREATE_DEDICATED_MEMORY_BIT flag
or those automatically decided to put into dedicated allocations, e.g. due to its
large size or recommended by VK_KHR_dedicated_allocation extension.
Margins are also not active in custom pools created with #VMA_POOL_CREATE_BUDDY_ALGORITHM_BIT flag.
Margins appear in [JSON dump](@ref statistics_json_dump) as part of free space.
Note that enabling margins increases memory usage and fragmentation.
\section debugging_memory_usage_corruption_detection Corruption detection
You can additionally define macro `VMA_DEBUG_DETECT_CORRUPTION` to 1 to enable validation
of contents of the margins.
\code
#define VMA_DEBUG_MARGIN 16
#define VMA_DEBUG_DETECT_CORRUPTION 1
#include "vk_mem_alloc.h"
\endcode
When this feature is enabled, number of bytes specified as `VMA_DEBUG_MARGIN`
(it must be multiply of 4) before and after every allocation is filled with a magic number.
This idea is also know as "canary".
Memory is automatically mapped and unmapped if necessary.
This number is validated automatically when the allocation is destroyed.
If it's not equal to the expected value, `VMA_ASSERT()` is executed.
It clearly means that either CPU or GPU overwritten the memory outside of boundaries of the allocation,
which indicates a serious bug.
You can also explicitly request checking margins of all allocations in all memory blocks
that belong to specified memory types by using function vmaCheckCorruption(),
or in memory blocks that belong to specified custom pool, by using function
vmaCheckPoolCorruption().
Margin validation (corruption detection) works only for memory types that are
`HOST_VISIBLE` and `HOST_COHERENT`.
\page record_and_replay Record and replay
\section record_and_replay_introduction Introduction
While using the library, sequence of calls to its functions together with their
parameters can be recorded to a file and later replayed using standalone player
application. It can be useful to:
- Test correctness - check if same sequence of calls will not cause crash or
failures on a target platform.
- Gather statistics - see number of allocations, peak memory usage, number of
calls etc.
- Benchmark performance - see how much time it takes to replay the whole
sequence.
\section record_and_replay_usage Usage
<b>To record sequence of calls to a file:</b> Fill in
VmaAllocatorCreateInfo::pRecordSettings member while creating #VmaAllocator
object. File is opened and written during whole lifetime of the allocator.
<b>To replay file:</b> Use VmaReplay - standalone command-line program.
Precompiled binary can be found in "bin" directory.
Its source can be found in "src/VmaReplay" directory.
Its project is generated by Premake.
Command line syntax is printed when the program is launched without parameters.
Basic usage:
VmaReplay.exe MyRecording.csv
<b>Documentation of file format</b> can be found in file: "docs/Recording file format.md".
It's a human-readable, text file in CSV format (Comma Separated Values).
\section record_and_replay_additional_considerations Additional considerations
- Replaying file that was recorded on a different GPU (with different parameters
like `bufferImageGranularity`, `nonCoherentAtomSize`, and especially different
set of memory heaps and types) may give different performance and memory usage
results, as well as issue some warnings and errors.
- Current implementation of recording in VMA, as well as VmaReplay application, is
coded and tested only on Windows. Inclusion of recording code is driven by
`VMA_RECORDING_ENABLED` macro. Support for other platforms should be easy to
add. Contributions are welcomed.
- Currently calls to vmaDefragment() function are not recorded.
\page usage_patterns Recommended usage patterns
See also slides from talk:
[Sawicki, Adam. Advanced Graphics Techniques Tutorial: Memory management in Vulkan and DX12. Game Developers Conference, 2018](https://www.gdcvault.com/play/1025458/Advanced-Graphics-Techniques-Tutorial-New)
\section usage_patterns_simple Simple patterns
\subsection usage_patterns_simple_render_targets Render targets
<b>When:</b>
Any resources that you frequently write and read on GPU,
e.g. images used as color attachments (aka "render targets"), depth-stencil attachments,
images/buffers used as storage image/buffer (aka "Unordered Access View (UAV)").
<b>What to do:</b>
Create them in video memory that is fastest to access from GPU using
#VMA_MEMORY_USAGE_GPU_ONLY.
Consider using [VK_KHR_dedicated_allocation](@ref vk_khr_dedicated_allocation) extension
and/or manually creating them as dedicated allocations using #VMA_ALLOCATION_CREATE_DEDICATED_MEMORY_BIT,
especially if they are large or if you plan to destroy and recreate them e.g. when
display resolution changes.
Prefer to create such resources first and all other GPU resources (like textures and vertex buffers) later.
\subsection usage_patterns_simple_immutable_resources Immutable resources
<b>When:</b>
Any resources that you fill on CPU only once (aka "immutable") or infrequently
and then read frequently on GPU,
e.g. textures, vertex and index buffers, constant buffers that don't change often.
<b>What to do:</b>
Create them in video memory that is fastest to access from GPU using
#VMA_MEMORY_USAGE_GPU_ONLY.
To initialize content of such resource, create a CPU-side (aka "staging") copy of it
in system memory - #VMA_MEMORY_USAGE_CPU_ONLY, map it, fill it,
and submit a transfer from it to the GPU resource.
You can keep the staging copy if you need it for another upload transfer in the future.
If you don't, you can destroy it or reuse this buffer for uploading different resource
after the transfer finishes.
Prefer to create just buffers in system memory rather than images, even for uploading textures.
Use `vkCmdCopyBufferToImage()`.
Dont use images with `VK_IMAGE_TILING_LINEAR`.
\subsection usage_patterns_dynamic_resources Dynamic resources
<b>When:</b>
Any resources that change frequently (aka "dynamic"), e.g. every frame or every draw call,
written on CPU, read on GPU.
<b>What to do:</b>
Create them using #VMA_MEMORY_USAGE_CPU_TO_GPU.
You can map it and write to it directly on CPU, as well as read from it on GPU.
This is a more complex situation. Different solutions are possible,
and the best one depends on specific GPU type, but you can use this simple approach for the start.
Prefer to write to such resource sequentially (e.g. using `memcpy`).
Don't perform random access or any reads from it on CPU, as it may be very slow.
\subsection usage_patterns_readback Readback
<b>When:</b>
Resources that contain data written by GPU that you want to read back on CPU,
e.g. results of some computations.
<b>What to do:</b>
Create them using #VMA_MEMORY_USAGE_GPU_TO_CPU.
You can write to them directly on GPU, as well as map and read them on CPU.
\section usage_patterns_advanced Advanced patterns
\subsection usage_patterns_integrated_graphics Detecting integrated graphics
You can support integrated graphics (like Intel HD Graphics, AMD APU) better
by detecting it in Vulkan.
To do it, call `vkGetPhysicalDeviceProperties()`, inspect
`VkPhysicalDeviceProperties::deviceType` and look for `VK_PHYSICAL_DEVICE_TYPE_INTEGRATED_GPU`.
When you find it, you can assume that memory is unified and all memory types are comparably fast
to access from GPU, regardless of `VK_MEMORY_PROPERTY_DEVICE_LOCAL_BIT`.
You can then sum up sizes of all available memory heaps and treat them as useful for
your GPU resources, instead of only `DEVICE_LOCAL` ones.
You can also prefer to create your resources in memory types that are `HOST_VISIBLE` to map them
directly instead of submitting explicit transfer (see below).
\subsection usage_patterns_direct_vs_transfer Direct access versus transfer
For resources that you frequently write on CPU and read on GPU, many solutions are possible:
-# Create one copy in video memory using #VMA_MEMORY_USAGE_GPU_ONLY,
second copy in system memory using #VMA_MEMORY_USAGE_CPU_ONLY and submit explicit tranfer each time.
-# Create just single copy using #VMA_MEMORY_USAGE_CPU_TO_GPU, map it and fill it on CPU,
read it directly on GPU.
-# Create just single copy using #VMA_MEMORY_USAGE_CPU_ONLY, map it and fill it on CPU,
read it directly on GPU.
Which solution is the most efficient depends on your resource and especially on the GPU.
It is best to measure it and then make the decision.
Some general recommendations:
- On integrated graphics use (2) or (3) to avoid unnecesary time and memory overhead
related to using a second copy and making transfer.
- For small resources (e.g. constant buffers) use (2).
Discrete AMD cards have special 256 MiB pool of video memory that is directly mappable.
Even if the resource ends up in system memory, its data may be cached on GPU after first
fetch over PCIe bus.
- For larger resources (e.g. textures), decide between (1) and (2).
You may want to differentiate NVIDIA and AMD, e.g. by looking for memory type that is
both `DEVICE_LOCAL` and `HOST_VISIBLE`. When you find it, use (2), otherwise use (1).
Similarly, for resources that you frequently write on GPU and read on CPU, multiple
solutions are possible:
-# Create one copy in video memory using #VMA_MEMORY_USAGE_GPU_ONLY,
second copy in system memory using #VMA_MEMORY_USAGE_GPU_TO_CPU and submit explicit tranfer each time.
-# Create just single copy using #VMA_MEMORY_USAGE_GPU_TO_CPU, write to it directly on GPU,
map it and read it on CPU.
You should take some measurements to decide which option is faster in case of your specific
resource.
If you don't want to specialize your code for specific types of GPUs, you can still make
an simple optimization for cases when your resource ends up in mappable memory to use it
directly in this case instead of creating CPU-side staging copy.
For details see [Finding out if memory is mappable](@ref memory_mapping_finding_if_memory_mappable).
\page configuration Configuration
Please check "CONFIGURATION SECTION" in the code to find macros that you can define
before each include of this file or change directly in this file to provide
your own implementation of basic facilities like assert, `min()` and `max()` functions,
mutex, atomic etc.
The library uses its own implementation of containers by default, but you can switch to using
STL containers instead.
\section config_Vulkan_functions Pointers to Vulkan functions
The library uses Vulkan functions straight from the `vulkan.h` header by default.
If you want to provide your own pointers to these functions, e.g. fetched using
`vkGetInstanceProcAddr()` and `vkGetDeviceProcAddr()`:
-# Define `VMA_STATIC_VULKAN_FUNCTIONS 0`.
-# Provide valid pointers through VmaAllocatorCreateInfo::pVulkanFunctions.
\section custom_memory_allocator Custom host memory allocator
If you use custom allocator for CPU memory rather than default operator `new`
and `delete` from C++, you can make this library using your allocator as well
by filling optional member VmaAllocatorCreateInfo::pAllocationCallbacks. These
functions will be passed to Vulkan, as well as used by the library itself to
make any CPU-side allocations.
\section allocation_callbacks Device memory allocation callbacks
The library makes calls to `vkAllocateMemory()` and `vkFreeMemory()` internally.
You can setup callbacks to be informed about these calls, e.g. for the purpose
of gathering some statistics. To do it, fill optional member
VmaAllocatorCreateInfo::pDeviceMemoryCallbacks.
\section heap_memory_limit Device heap memory limit
When device memory of certain heap runs out of free space, new allocations may
fail (returning error code) or they may succeed, silently pushing some existing
memory blocks from GPU VRAM to system RAM (which degrades performance). This
behavior is implementation-dependant - it depends on GPU vendor and graphics
driver.
On AMD cards it can be controlled while creating Vulkan device object by using
VK_AMD_memory_allocation_behavior extension, if available.
Alternatively, if you want to test how your program behaves with limited amount of Vulkan device
memory available without switching your graphics card to one that really has
smaller VRAM, you can use a feature of this library intended for this purpose.
To do it, fill optional member VmaAllocatorCreateInfo::pHeapSizeLimit.
\page vk_khr_dedicated_allocation VK_KHR_dedicated_allocation
VK_KHR_dedicated_allocation is a Vulkan extension which can be used to improve
performance on some GPUs. It augments Vulkan API with possibility to query
driver whether it prefers particular buffer or image to have its own, dedicated
allocation (separate `VkDeviceMemory` block) for better efficiency - to be able
to do some internal optimizations.
The extension is supported by this library. It will be used automatically when
enabled. To enable it:
1 . When creating Vulkan device, check if following 2 device extensions are
supported (call `vkEnumerateDeviceExtensionProperties()`).
If yes, enable them (fill `VkDeviceCreateInfo::ppEnabledExtensionNames`).
- VK_KHR_get_memory_requirements2
- VK_KHR_dedicated_allocation
If you enabled these extensions:
2 . Use #VMA_ALLOCATOR_CREATE_KHR_DEDICATED_ALLOCATION_BIT flag when creating
your #VmaAllocator`to inform the library that you enabled required extensions
and you want the library to use them.
\code
allocatorInfo.flags |= VMA_ALLOCATOR_CREATE_KHR_DEDICATED_ALLOCATION_BIT;
vmaCreateAllocator(&allocatorInfo, &allocator);
\endcode
That's all. The extension will be automatically used whenever you create a
buffer using vmaCreateBuffer() or image using vmaCreateImage().
When using the extension together with Vulkan Validation Layer, you will receive
warnings like this:
vkBindBufferMemory(): Binding memory to buffer 0x33 but vkGetBufferMemoryRequirements() has not been called on that buffer.
It is OK, you should just ignore it. It happens because you use function
`vkGetBufferMemoryRequirements2KHR()` instead of standard
`vkGetBufferMemoryRequirements()`, while the validation layer seems to be
unaware of it.
To learn more about this extension, see:
- [VK_KHR_dedicated_allocation in Vulkan specification](https://www.khronos.org/registry/vulkan/specs/1.0-extensions/html/vkspec.html#VK_KHR_dedicated_allocation)
- [VK_KHR_dedicated_allocation unofficial manual](http://asawicki.info/articles/VK_KHR_dedicated_allocation.php5)
\page general_considerations General considerations
\section general_considerations_thread_safety Thread safety
- The library has no global state, so separate #VmaAllocator objects can be used
independently.
There should be no need to create multiple such objects though - one per `VkDevice` is enough.
- By default, all calls to functions that take #VmaAllocator as first parameter
are safe to call from multiple threads simultaneously because they are
synchronized internally when needed.
- When the allocator is created with #VMA_ALLOCATOR_CREATE_EXTERNALLY_SYNCHRONIZED_BIT
flag, calls to functions that take such #VmaAllocator object must be
synchronized externally.
- Access to a #VmaAllocation object must be externally synchronized. For example,
you must not call vmaGetAllocationInfo() and vmaMapMemory() from different
threads at the same time if you pass the same #VmaAllocation object to these
functions.
\section general_considerations_validation_layer_warnings Validation layer warnings
When using this library, you can meet following types of warnings issued by
Vulkan validation layer. They don't necessarily indicate a bug, so you may need
to just ignore them.
- *vkBindBufferMemory(): Binding memory to buffer 0xeb8e4 but vkGetBufferMemoryRequirements() has not been called on that buffer.*
- It happens when VK_KHR_dedicated_allocation extension is enabled.
`vkGetBufferMemoryRequirements2KHR` function is used instead, while validation layer seems to be unaware of it.
- *Mapping an image with layout VK_IMAGE_LAYOUT_DEPTH_STENCIL_ATTACHMENT_OPTIMAL can result in undefined behavior if this memory is used by the device. Only GENERAL or PREINITIALIZED should be used.*
- It happens when you map a buffer or image, because the library maps entire
`VkDeviceMemory` block, where different types of images and buffers may end
up together, especially on GPUs with unified memory like Intel.
- *Non-linear image 0xebc91 is aliased with linear buffer 0xeb8e4 which may indicate a bug.*
- It happens when you use lost allocations, and a new image or buffer is
created in place of an existing object that bacame lost.
- It may happen also when you use [defragmentation](@ref defragmentation).
\section general_considerations_allocation_algorithm Allocation algorithm
The library uses following algorithm for allocation, in order:
-# Try to find free range of memory in existing blocks.
-# If failed, try to create a new block of `VkDeviceMemory`, with preferred block size.
-# If failed, try to create such block with size/2, size/4, size/8.
-# If failed and #VMA_ALLOCATION_CREATE_CAN_MAKE_OTHER_LOST_BIT flag was
specified, try to find space in existing blocks, possilby making some other
allocations lost.
-# If failed, try to allocate separate `VkDeviceMemory` for this allocation,
just like when you use #VMA_ALLOCATION_CREATE_DEDICATED_MEMORY_BIT.
-# If failed, choose other memory type that meets the requirements specified in
VmaAllocationCreateInfo and go to point 1.
-# If failed, return `VK_ERROR_OUT_OF_DEVICE_MEMORY`.
\section general_considerations_features_not_supported Features not supported
Features deliberately excluded from the scope of this library:
- Data transfer. Uploading (straming) and downloading data of buffers and images
between CPU and GPU memory and related synchronization is responsibility of the user.
Defining some "texture" object that would automatically stream its data from a
staging copy in CPU memory to GPU memory would rather be a feature of another,
higher-level library implemented on top of VMA.
- Allocations for imported/exported external memory. They tend to require
explicit memory type index and dedicated allocation anyway, so they don't
interact with main features of this library. Such special purpose allocations
should be made manually, using `vkCreateBuffer()` and `vkAllocateMemory()`.
- Recreation of buffers and images. Although the library has functions for
buffer and image creation (vmaCreateBuffer(), vmaCreateImage()), you need to
recreate these objects yourself after defragmentation. That's because the big
structures `VkBufferCreateInfo`, `VkImageCreateInfo` are not stored in
#VmaAllocation object.
- Handling CPU memory allocation failures. When dynamically creating small C++
objects in CPU memory (not Vulkan memory), allocation failures are not checked
and handled gracefully, because that would complicate code significantly and
is usually not needed in desktop PC applications anyway.
- Code free of any compiler warnings. Maintaining the library to compile and
work correctly on so many different platforms is hard enough. Being free of
any warnings, on any version of any compiler, is simply not feasible.
- This is a C++ library with C interface.
Bindings or ports to any other programming languages are welcomed as external projects and
are not going to be included into this repository.
*/
/*
Define this macro to 0/1 to disable/enable support for recording functionality,
available through VmaAllocatorCreateInfo::pRecordSettings.
*/
#ifndef VMA_RECORDING_ENABLED
#ifdef _WIN32
#define VMA_RECORDING_ENABLED 1
#else
#define VMA_RECORDING_ENABLED 0
#endif
#endif
#ifndef NOMINMAX
#define NOMINMAX // For windows.h
#endif
#ifndef VULKAN_H_
#include <vulkan/vulkan.h>
#endif
#if VMA_RECORDING_ENABLED
#include <windows.h>
#endif
#if !defined(VMA_DEDICATED_ALLOCATION)
#if VK_KHR_get_memory_requirements2 && VK_KHR_dedicated_allocation
#define VMA_DEDICATED_ALLOCATION 1
#else
#define VMA_DEDICATED_ALLOCATION 0
#endif
#endif
/** \struct VmaAllocator
\brief Represents main object of this library initialized.
Fill structure #VmaAllocatorCreateInfo and call function vmaCreateAllocator() to create it.
Call function vmaDestroyAllocator() to destroy it.
It is recommended to create just one object of this type per `VkDevice` object,
right after Vulkan is initialized and keep it alive until before Vulkan device is destroyed.
*/
VK_DEFINE_HANDLE(VmaAllocator)
/// Callback function called after successful vkAllocateMemory.
typedef void (VKAPI_PTR *PFN_vmaAllocateDeviceMemoryFunction)(
VmaAllocator allocator,
uint32_t memoryType,
VkDeviceMemory memory,
VkDeviceSize size);
/// Callback function called before vkFreeMemory.
typedef void (VKAPI_PTR *PFN_vmaFreeDeviceMemoryFunction)(
VmaAllocator allocator,
uint32_t memoryType,
VkDeviceMemory memory,
VkDeviceSize size);
/** \brief Set of callbacks that the library will call for `vkAllocateMemory` and `vkFreeMemory`.
Provided for informative purpose, e.g. to gather statistics about number of
allocations or total amount of memory allocated in Vulkan.
Used in VmaAllocatorCreateInfo::pDeviceMemoryCallbacks.
*/
typedef struct VmaDeviceMemoryCallbacks {
/// Optional, can be null.
PFN_vmaAllocateDeviceMemoryFunction pfnAllocate;
/// Optional, can be null.
PFN_vmaFreeDeviceMemoryFunction pfnFree;
} VmaDeviceMemoryCallbacks;
/// Flags for created #VmaAllocator.
typedef enum VmaAllocatorCreateFlagBits {
/** \brief Allocator and all objects created from it will not be synchronized internally, so you must guarantee they are used from only one thread at a time or synchronized externally by you.
Using this flag may increase performance because internal mutexes are not used.
*/
VMA_ALLOCATOR_CREATE_EXTERNALLY_SYNCHRONIZED_BIT = 0x00000001,
/** \brief Enables usage of VK_KHR_dedicated_allocation extension.
Using this extenion will automatically allocate dedicated blocks of memory for
some buffers and images instead of suballocating place for them out of bigger
memory blocks (as if you explicitly used #VMA_ALLOCATION_CREATE_DEDICATED_MEMORY_BIT
flag) when it is recommended by the driver. It may improve performance on some
GPUs.
You may set this flag only if you found out that following device extensions are
supported, you enabled them while creating Vulkan device passed as
VmaAllocatorCreateInfo::device, and you want them to be used internally by this
library:
- VK_KHR_get_memory_requirements2
- VK_KHR_dedicated_allocation
When this flag is set, you can experience following warnings reported by Vulkan
validation layer. You can ignore them.
> vkBindBufferMemory(): Binding memory to buffer 0x2d but vkGetBufferMemoryRequirements() has not been called on that buffer.
*/
VMA_ALLOCATOR_CREATE_KHR_DEDICATED_ALLOCATION_BIT = 0x00000002,
VMA_ALLOCATOR_CREATE_FLAG_BITS_MAX_ENUM = 0x7FFFFFFF
} VmaAllocatorCreateFlagBits;
typedef VkFlags VmaAllocatorCreateFlags;
/** \brief Pointers to some Vulkan functions - a subset used by the library.
Used in VmaAllocatorCreateInfo::pVulkanFunctions.
*/
typedef struct VmaVulkanFunctions {
PFN_vkGetPhysicalDeviceProperties vkGetPhysicalDeviceProperties;
PFN_vkGetPhysicalDeviceMemoryProperties vkGetPhysicalDeviceMemoryProperties;
PFN_vkAllocateMemory vkAllocateMemory;
PFN_vkFreeMemory vkFreeMemory;
PFN_vkMapMemory vkMapMemory;
PFN_vkUnmapMemory vkUnmapMemory;
PFN_vkFlushMappedMemoryRanges vkFlushMappedMemoryRanges;
PFN_vkInvalidateMappedMemoryRanges vkInvalidateMappedMemoryRanges;
PFN_vkBindBufferMemory vkBindBufferMemory;
PFN_vkBindImageMemory vkBindImageMemory;
PFN_vkGetBufferMemoryRequirements vkGetBufferMemoryRequirements;
PFN_vkGetImageMemoryRequirements vkGetImageMemoryRequirements;
PFN_vkCreateBuffer vkCreateBuffer;
PFN_vkDestroyBuffer vkDestroyBuffer;
PFN_vkCreateImage vkCreateImage;
PFN_vkDestroyImage vkDestroyImage;
PFN_vkCmdCopyBuffer vkCmdCopyBuffer;
#if VMA_DEDICATED_ALLOCATION
PFN_vkGetBufferMemoryRequirements2KHR vkGetBufferMemoryRequirements2KHR;
PFN_vkGetImageMemoryRequirements2KHR vkGetImageMemoryRequirements2KHR;
#endif
} VmaVulkanFunctions;
/// Flags to be used in VmaRecordSettings::flags.
typedef enum VmaRecordFlagBits {
/** \brief Enables flush after recording every function call.
Enable it if you expect your application to crash, which may leave recording file truncated.
It may degrade performance though.
*/
VMA_RECORD_FLUSH_AFTER_CALL_BIT = 0x00000001,
VMA_RECORD_FLAG_BITS_MAX_ENUM = 0x7FFFFFFF
} VmaRecordFlagBits;
typedef VkFlags VmaRecordFlags;
/// Parameters for recording calls to VMA functions. To be used in VmaAllocatorCreateInfo::pRecordSettings.
typedef struct VmaRecordSettings
{
/// Flags for recording. Use #VmaRecordFlagBits enum.
VmaRecordFlags flags;
/** \brief Path to the file that should be written by the recording.
Suggested extension: "csv".
If the file already exists, it will be overwritten.
It will be opened for the whole time #VmaAllocator object is alive.
If opening this file fails, creation of the whole allocator object fails.
*/
const char* pFilePath;
} VmaRecordSettings;
/// Description of a Allocator to be created.
typedef struct VmaAllocatorCreateInfo
{
/// Flags for created allocator. Use #VmaAllocatorCreateFlagBits enum.
VmaAllocatorCreateFlags flags;
/// Vulkan physical device.
/** It must be valid throughout whole lifetime of created allocator. */
VkPhysicalDevice physicalDevice;
/// Vulkan device.
/** It must be valid throughout whole lifetime of created allocator. */
VkDevice device;
/// Preferred size of a single `VkDeviceMemory` block to be allocated from large heaps > 1 GiB. Optional.
/** Set to 0 to use default, which is currently 256 MiB. */
VkDeviceSize preferredLargeHeapBlockSize;
/// Custom CPU memory allocation callbacks. Optional.
/** Optional, can be null. When specified, will also be used for all CPU-side memory allocations. */
const VkAllocationCallbacks* pAllocationCallbacks;
/// Informative callbacks for `vkAllocateMemory`, `vkFreeMemory`. Optional.
/** Optional, can be null. */
const VmaDeviceMemoryCallbacks* pDeviceMemoryCallbacks;
/** \brief Maximum number of additional frames that are in use at the same time as current frame.
This value is used only when you make allocations with
VMA_ALLOCATION_CREATE_CAN_BECOME_LOST_BIT flag. Such allocation cannot become
lost if allocation.lastUseFrameIndex >= allocator.currentFrameIndex - frameInUseCount.
For example, if you double-buffer your command buffers, so resources used for
rendering in previous frame may still be in use by the GPU at the moment you
allocate resources needed for the current frame, set this value to 1.
If you want to allow any allocations other than used in the current frame to
become lost, set this value to 0.
*/
uint32_t frameInUseCount;
/** \brief Either null or a pointer to an array of limits on maximum number of bytes that can be allocated out of particular Vulkan memory heap.
If not NULL, it must be a pointer to an array of
`VkPhysicalDeviceMemoryProperties::memoryHeapCount` elements, defining limit on
maximum number of bytes that can be allocated out of particular Vulkan memory
heap.
Any of the elements may be equal to `VK_WHOLE_SIZE`, which means no limit on that
heap. This is also the default in case of `pHeapSizeLimit` = NULL.
If there is a limit defined for a heap:
- If user tries to allocate more memory from that heap using this allocator,
the allocation fails with `VK_ERROR_OUT_OF_DEVICE_MEMORY`.
- If the limit is smaller than heap size reported in `VkMemoryHeap::size`, the
value of this limit will be reported instead when using vmaGetMemoryProperties().
Warning! Using this feature may not be equivalent to installing a GPU with
smaller amount of memory, because graphics driver doesn't necessary fail new
allocations with `VK_ERROR_OUT_OF_DEVICE_MEMORY` result when memory capacity is
exceeded. It may return success and just silently migrate some device memory
blocks to system RAM. This driver behavior can also be controlled using
VK_AMD_memory_overallocation_behavior extension.
*/
const VkDeviceSize* pHeapSizeLimit;
/** \brief Pointers to Vulkan functions. Can be null if you leave define `VMA_STATIC_VULKAN_FUNCTIONS 1`.
If you leave define `VMA_STATIC_VULKAN_FUNCTIONS 1` in configuration section,
you can pass null as this member, because the library will fetch pointers to
Vulkan functions internally in a static way, like:
vulkanFunctions.vkAllocateMemory = &vkAllocateMemory;
Fill this member if you want to provide your own pointers to Vulkan functions,
e.g. fetched using `vkGetInstanceProcAddr()` and `vkGetDeviceProcAddr()`.
*/
const VmaVulkanFunctions* pVulkanFunctions;
/** \brief Parameters for recording of VMA calls. Can be null.
If not null, it enables recording of calls to VMA functions to a file.
If support for recording is not enabled using `VMA_RECORDING_ENABLED` macro,
creation of the allocator object fails with `VK_ERROR_FEATURE_NOT_PRESENT`.
*/
const VmaRecordSettings* pRecordSettings;
} VmaAllocatorCreateInfo;
/// Creates Allocator object.
VkResult vmaCreateAllocator(
const VmaAllocatorCreateInfo* pCreateInfo,
VmaAllocator* pAllocator);
/// Destroys allocator object.
void vmaDestroyAllocator(
VmaAllocator allocator);
/**
PhysicalDeviceProperties are fetched from physicalDevice by the allocator.
You can access it here, without fetching it again on your own.
*/
void vmaGetPhysicalDeviceProperties(
VmaAllocator allocator,
const VkPhysicalDeviceProperties** ppPhysicalDeviceProperties);
/**
PhysicalDeviceMemoryProperties are fetched from physicalDevice by the allocator.
You can access it here, without fetching it again on your own.
*/
void vmaGetMemoryProperties(
VmaAllocator allocator,
const VkPhysicalDeviceMemoryProperties** ppPhysicalDeviceMemoryProperties);
/**
\brief Given Memory Type Index, returns Property Flags of this memory type.
This is just a convenience function. Same information can be obtained using
vmaGetMemoryProperties().
*/
void vmaGetMemoryTypeProperties(
VmaAllocator allocator,
uint32_t memoryTypeIndex,
VkMemoryPropertyFlags* pFlags);
/** \brief Sets index of the current frame.
This function must be used if you make allocations with
#VMA_ALLOCATION_CREATE_CAN_BECOME_LOST_BIT and
#VMA_ALLOCATION_CREATE_CAN_MAKE_OTHER_LOST_BIT flags to inform the allocator
when a new frame begins. Allocations queried using vmaGetAllocationInfo() cannot
become lost in the current frame.
*/
void vmaSetCurrentFrameIndex(
VmaAllocator allocator,
uint32_t frameIndex);
/** \brief Calculated statistics of memory usage in entire allocator.
*/
typedef struct VmaStatInfo
{
/// Number of `VkDeviceMemory` Vulkan memory blocks allocated.
uint32_t blockCount;
/// Number of #VmaAllocation allocation objects allocated.
uint32_t allocationCount;
/// Number of free ranges of memory between allocations.
uint32_t unusedRangeCount;
/// Total number of bytes occupied by all allocations.
VkDeviceSize usedBytes;
/// Total number of bytes occupied by unused ranges.
VkDeviceSize unusedBytes;
VkDeviceSize allocationSizeMin, allocationSizeAvg, allocationSizeMax;
VkDeviceSize unusedRangeSizeMin, unusedRangeSizeAvg, unusedRangeSizeMax;
} VmaStatInfo;
/// General statistics from current state of Allocator.
typedef struct VmaStats
{
VmaStatInfo memoryType[VK_MAX_MEMORY_TYPES];
VmaStatInfo memoryHeap[VK_MAX_MEMORY_HEAPS];
VmaStatInfo total;
} VmaStats;
/// Retrieves statistics from current state of the Allocator.
void vmaCalculateStats(
VmaAllocator allocator,
VmaStats* pStats);
#ifndef VMA_STATS_STRING_ENABLED
#define VMA_STATS_STRING_ENABLED 1
#endif
#if VMA_STATS_STRING_ENABLED
/// Builds and returns statistics as string in JSON format.
/** @param[out] ppStatsString Must be freed using vmaFreeStatsString() function.
*/
void vmaBuildStatsString(
VmaAllocator allocator,
char** ppStatsString,
VkBool32 detailedMap);
void vmaFreeStatsString(
VmaAllocator allocator,
char* pStatsString);
#endif // #if VMA_STATS_STRING_ENABLED
/** \struct VmaPool
\brief Represents custom memory pool
Fill structure VmaPoolCreateInfo and call function vmaCreatePool() to create it.
Call function vmaDestroyPool() to destroy it.
For more information see [Custom memory pools](@ref choosing_memory_type_custom_memory_pools).
*/
VK_DEFINE_HANDLE(VmaPool)
typedef enum VmaMemoryUsage
{
/** No intended memory usage specified.
Use other members of VmaAllocationCreateInfo to specify your requirements.
*/
VMA_MEMORY_USAGE_UNKNOWN = 0,
/** Memory will be used on device only, so fast access from the device is preferred.
It usually means device-local GPU (video) memory.
No need to be mappable on host.
It is roughly equivalent of `D3D12_HEAP_TYPE_DEFAULT`.
Usage:
- Resources written and read by device, e.g. images used as attachments.
- Resources transferred from host once (immutable) or infrequently and read by
device multiple times, e.g. textures to be sampled, vertex buffers, uniform
(constant) buffers, and majority of other types of resources used on GPU.
Allocation may still end up in `HOST_VISIBLE` memory on some implementations.
In such case, you are free to map it.
You can use #VMA_ALLOCATION_CREATE_MAPPED_BIT with this usage type.
*/
VMA_MEMORY_USAGE_GPU_ONLY = 1,
/** Memory will be mappable on host.
It usually means CPU (system) memory.
Guarantees to be `HOST_VISIBLE` and `HOST_COHERENT`.
CPU access is typically uncached. Writes may be write-combined.
Resources created in this pool may still be accessible to the device, but access to them can be slow.
It is roughly equivalent of `D3D12_HEAP_TYPE_UPLOAD`.
Usage: Staging copy of resources used as transfer source.
*/
VMA_MEMORY_USAGE_CPU_ONLY = 2,
/**
Memory that is both mappable on host (guarantees to be `HOST_VISIBLE`) and preferably fast to access by GPU.
CPU access is typically uncached. Writes may be write-combined.
Usage: Resources written frequently by host (dynamic), read by device. E.g. textures, vertex buffers, uniform buffers updated every frame or every draw call.
*/
VMA_MEMORY_USAGE_CPU_TO_GPU = 3,
/** Memory mappable on host (guarantees to be `HOST_VISIBLE`) and cached.
It is roughly equivalent of `D3D12_HEAP_TYPE_READBACK`.
Usage:
- Resources written by device, read by host - results of some computations, e.g. screen capture, average scene luminance for HDR tone mapping.
- Any resources read or accessed randomly on host, e.g. CPU-side copy of vertex buffer used as source of transfer, but also used for collision detection.
*/
VMA_MEMORY_USAGE_GPU_TO_CPU = 4,
VMA_MEMORY_USAGE_MAX_ENUM = 0x7FFFFFFF
} VmaMemoryUsage;
/// Flags to be passed as VmaAllocationCreateInfo::flags.
typedef enum VmaAllocationCreateFlagBits {
/** \brief Set this flag if the allocation should have its own memory block.
Use it for special, big resources, like fullscreen images used as attachments.
You should not use this flag if VmaAllocationCreateInfo::pool is not null.
*/
VMA_ALLOCATION_CREATE_DEDICATED_MEMORY_BIT = 0x00000001,
/** \brief Set this flag to only try to allocate from existing `VkDeviceMemory` blocks and never create new such block.
If new allocation cannot be placed in any of the existing blocks, allocation
fails with `VK_ERROR_OUT_OF_DEVICE_MEMORY` error.
You should not use #VMA_ALLOCATION_CREATE_DEDICATED_MEMORY_BIT and
#VMA_ALLOCATION_CREATE_NEVER_ALLOCATE_BIT at the same time. It makes no sense.
If VmaAllocationCreateInfo::pool is not null, this flag is implied and ignored. */
VMA_ALLOCATION_CREATE_NEVER_ALLOCATE_BIT = 0x00000002,
/** \brief Set this flag to use a memory that will be persistently mapped and retrieve pointer to it.
Pointer to mapped memory will be returned through VmaAllocationInfo::pMappedData.
Is it valid to use this flag for allocation made from memory type that is not
`HOST_VISIBLE`. This flag is then ignored and memory is not mapped. This is
useful if you need an allocation that is efficient to use on GPU
(`DEVICE_LOCAL`) and still want to map it directly if possible on platforms that
support it (e.g. Intel GPU).
You should not use this flag together with #VMA_ALLOCATION_CREATE_CAN_BECOME_LOST_BIT.
*/
VMA_ALLOCATION_CREATE_MAPPED_BIT = 0x00000004,
/** Allocation created with this flag can become lost as a result of another
allocation with #VMA_ALLOCATION_CREATE_CAN_MAKE_OTHER_LOST_BIT flag, so you
must check it before use.
To check if allocation is not lost, call vmaGetAllocationInfo() and check if
VmaAllocationInfo::deviceMemory is not `VK_NULL_HANDLE`.
For details about supporting lost allocations, see Lost Allocations
chapter of User Guide on Main Page.
You should not use this flag together with #VMA_ALLOCATION_CREATE_MAPPED_BIT.
*/
VMA_ALLOCATION_CREATE_CAN_BECOME_LOST_BIT = 0x00000008,
/** While creating allocation using this flag, other allocations that were
created with flag #VMA_ALLOCATION_CREATE_CAN_BECOME_LOST_BIT can become lost.
For details about supporting lost allocations, see Lost Allocations
chapter of User Guide on Main Page.
*/
VMA_ALLOCATION_CREATE_CAN_MAKE_OTHER_LOST_BIT = 0x00000010,
/** Set this flag to treat VmaAllocationCreateInfo::pUserData as pointer to a
null-terminated string. Instead of copying pointer value, a local copy of the
string is made and stored in allocation's `pUserData`. The string is automatically
freed together with the allocation. It is also used in vmaBuildStatsString().
*/
VMA_ALLOCATION_CREATE_USER_DATA_COPY_STRING_BIT = 0x00000020,
/** Allocation will be created from upper stack in a double stack pool.
This flag is only allowed for custom pools created with #VMA_POOL_CREATE_LINEAR_ALGORITHM_BIT flag.
*/
VMA_ALLOCATION_CREATE_UPPER_ADDRESS_BIT = 0x00000040,
/** Create both buffer/image and allocation, but don't bind them together.
It is useful when you want to bind yourself to do some more advanced binding, e.g. using some extensions.
The flag is meaningful only with functions that bind by default: vmaCreateBuffer(), vmaCreateImage().
Otherwise it is ignored.
*/
VMA_ALLOCATION_CREATE_DONT_BIND_BIT = 0x00000080,
/** Allocation strategy that chooses smallest possible free range for the
allocation.
*/
VMA_ALLOCATION_CREATE_STRATEGY_BEST_FIT_BIT = 0x00010000,
/** Allocation strategy that chooses biggest possible free range for the
allocation.
*/
VMA_ALLOCATION_CREATE_STRATEGY_WORST_FIT_BIT = 0x00020000,
/** Allocation strategy that chooses first suitable free range for the
allocation.
"First" doesn't necessarily means the one with smallest offset in memory,
but rather the one that is easiest and fastest to find.
*/
VMA_ALLOCATION_CREATE_STRATEGY_FIRST_FIT_BIT = 0x00040000,
/** Allocation strategy that tries to minimize memory usage.
*/
VMA_ALLOCATION_CREATE_STRATEGY_MIN_MEMORY_BIT = VMA_ALLOCATION_CREATE_STRATEGY_BEST_FIT_BIT,
/** Allocation strategy that tries to minimize allocation time.
*/
VMA_ALLOCATION_CREATE_STRATEGY_MIN_TIME_BIT = VMA_ALLOCATION_CREATE_STRATEGY_FIRST_FIT_BIT,
/** Allocation strategy that tries to minimize memory fragmentation.
*/
VMA_ALLOCATION_CREATE_STRATEGY_MIN_FRAGMENTATION_BIT = VMA_ALLOCATION_CREATE_STRATEGY_WORST_FIT_BIT,
/** A bit mask to extract only `STRATEGY` bits from entire set of flags.
*/
VMA_ALLOCATION_CREATE_STRATEGY_MASK =
VMA_ALLOCATION_CREATE_STRATEGY_BEST_FIT_BIT |
VMA_ALLOCATION_CREATE_STRATEGY_WORST_FIT_BIT |
VMA_ALLOCATION_CREATE_STRATEGY_FIRST_FIT_BIT,
VMA_ALLOCATION_CREATE_FLAG_BITS_MAX_ENUM = 0x7FFFFFFF
} VmaAllocationCreateFlagBits;
typedef VkFlags VmaAllocationCreateFlags;
typedef struct VmaAllocationCreateInfo
{
/// Use #VmaAllocationCreateFlagBits enum.
VmaAllocationCreateFlags flags;
/** \brief Intended usage of memory.
You can leave #VMA_MEMORY_USAGE_UNKNOWN if you specify memory requirements in other way. \n
If `pool` is not null, this member is ignored.
*/
VmaMemoryUsage usage;
/** \brief Flags that must be set in a Memory Type chosen for an allocation.
Leave 0 if you specify memory requirements in other way. \n
If `pool` is not null, this member is ignored.*/
VkMemoryPropertyFlags requiredFlags;
/** \brief Flags that preferably should be set in a memory type chosen for an allocation.
Set to 0 if no additional flags are prefered. \n
If `pool` is not null, this member is ignored. */
VkMemoryPropertyFlags preferredFlags;
/** \brief Bitmask containing one bit set for every memory type acceptable for this allocation.
Value 0 is equivalent to `UINT32_MAX` - it means any memory type is accepted if
it meets other requirements specified by this structure, with no further
restrictions on memory type index. \n
If `pool` is not null, this member is ignored.
*/
uint32_t memoryTypeBits;
/** \brief Pool that this allocation should be created in.
Leave `VK_NULL_HANDLE` to allocate from default pool. If not null, members:
`usage`, `requiredFlags`, `preferredFlags`, `memoryTypeBits` are ignored.
*/
VmaPool pool;
/** \brief Custom general-purpose pointer that will be stored in #VmaAllocation, can be read as VmaAllocationInfo::pUserData and changed using vmaSetAllocationUserData().
If #VMA_ALLOCATION_CREATE_USER_DATA_COPY_STRING_BIT is used, it must be either
null or pointer to a null-terminated string. The string will be then copied to
internal buffer, so it doesn't need to be valid after allocation call.
*/
void* pUserData;
} VmaAllocationCreateInfo;
/**
\brief Helps to find memoryTypeIndex, given memoryTypeBits and VmaAllocationCreateInfo.
This algorithm tries to find a memory type that:
- Is allowed by memoryTypeBits.
- Contains all the flags from pAllocationCreateInfo->requiredFlags.
- Matches intended usage.
- Has as many flags from pAllocationCreateInfo->preferredFlags as possible.
\return Returns VK_ERROR_FEATURE_NOT_PRESENT if not found. Receiving such result
from this function or any other allocating function probably means that your
device doesn't support any memory type with requested features for the specific
type of resource you want to use it for. Please check parameters of your
resource, like image layout (OPTIMAL versus LINEAR) or mip level count.
*/
VkResult vmaFindMemoryTypeIndex(
VmaAllocator allocator,
uint32_t memoryTypeBits,
const VmaAllocationCreateInfo* pAllocationCreateInfo,
uint32_t* pMemoryTypeIndex);
/**
\brief Helps to find memoryTypeIndex, given VkBufferCreateInfo and VmaAllocationCreateInfo.
It can be useful e.g. to determine value to be used as VmaPoolCreateInfo::memoryTypeIndex.
It internally creates a temporary, dummy buffer that never has memory bound.
It is just a convenience function, equivalent to calling:
- `vkCreateBuffer`
- `vkGetBufferMemoryRequirements`
- `vmaFindMemoryTypeIndex`
- `vkDestroyBuffer`
*/
VkResult vmaFindMemoryTypeIndexForBufferInfo(
VmaAllocator allocator,
const VkBufferCreateInfo* pBufferCreateInfo,
const VmaAllocationCreateInfo* pAllocationCreateInfo,
uint32_t* pMemoryTypeIndex);
/**
\brief Helps to find memoryTypeIndex, given VkImageCreateInfo and VmaAllocationCreateInfo.
It can be useful e.g. to determine value to be used as VmaPoolCreateInfo::memoryTypeIndex.
It internally creates a temporary, dummy image that never has memory bound.
It is just a convenience function, equivalent to calling:
- `vkCreateImage`
- `vkGetImageMemoryRequirements`
- `vmaFindMemoryTypeIndex`
- `vkDestroyImage`
*/
VkResult vmaFindMemoryTypeIndexForImageInfo(
VmaAllocator allocator,
const VkImageCreateInfo* pImageCreateInfo,
const VmaAllocationCreateInfo* pAllocationCreateInfo,
uint32_t* pMemoryTypeIndex);
/// Flags to be passed as VmaPoolCreateInfo::flags.
typedef enum VmaPoolCreateFlagBits {
/** \brief Use this flag if you always allocate only buffers and linear images or only optimal images out of this pool and so Buffer-Image Granularity can be ignored.
This is an optional optimization flag.
If you always allocate using vmaCreateBuffer(), vmaCreateImage(),
vmaAllocateMemoryForBuffer(), then you don't need to use it because allocator
knows exact type of your allocations so it can handle Buffer-Image Granularity
in the optimal way.
If you also allocate using vmaAllocateMemoryForImage() or vmaAllocateMemory(),
exact type of such allocations is not known, so allocator must be conservative
in handling Buffer-Image Granularity, which can lead to suboptimal allocation
(wasted memory). In that case, if you can make sure you always allocate only
buffers and linear images or only optimal images out of this pool, use this flag
to make allocator disregard Buffer-Image Granularity and so make allocations
faster and more optimal.
*/
VMA_POOL_CREATE_IGNORE_BUFFER_IMAGE_GRANULARITY_BIT = 0x00000002,
/** \brief Enables alternative, linear allocation algorithm in this pool.
Specify this flag to enable linear allocation algorithm, which always creates
new allocations after last one and doesn't reuse space from allocations freed in
between. It trades memory consumption for simplified algorithm and data
structure, which has better performance and uses less memory for metadata.
By using this flag, you can achieve behavior of free-at-once, stack,
ring buffer, and double stack. For details, see documentation chapter
\ref linear_algorithm.
When using this flag, you must specify VmaPoolCreateInfo::maxBlockCount == 1 (or 0 for default).
For more details, see [Linear allocation algorithm](@ref linear_algorithm).
*/
VMA_POOL_CREATE_LINEAR_ALGORITHM_BIT = 0x00000004,
/** \brief Enables alternative, buddy allocation algorithm in this pool.
It operates on a tree of blocks, each having size that is a power of two and
a half of its parent's size. Comparing to default algorithm, this one provides
faster allocation and deallocation and decreased external fragmentation,
at the expense of more memory wasted (internal fragmentation).
For more details, see [Buddy allocation algorithm](@ref buddy_algorithm).
*/
VMA_POOL_CREATE_BUDDY_ALGORITHM_BIT = 0x00000008,
/** Bit mask to extract only `ALGORITHM` bits from entire set of flags.
*/
VMA_POOL_CREATE_ALGORITHM_MASK =
VMA_POOL_CREATE_LINEAR_ALGORITHM_BIT |
VMA_POOL_CREATE_BUDDY_ALGORITHM_BIT,
VMA_POOL_CREATE_FLAG_BITS_MAX_ENUM = 0x7FFFFFFF
} VmaPoolCreateFlagBits;
typedef VkFlags VmaPoolCreateFlags;
/** \brief Describes parameter of created #VmaPool.
*/
typedef struct VmaPoolCreateInfo {
/** \brief Vulkan memory type index to allocate this pool from.
*/
uint32_t memoryTypeIndex;
/** \brief Use combination of #VmaPoolCreateFlagBits.
*/
VmaPoolCreateFlags flags;
/** \brief Size of a single `VkDeviceMemory` block to be allocated as part of this pool, in bytes. Optional.
Specify nonzero to set explicit, constant size of memory blocks used by this
pool.
Leave 0 to use default and let the library manage block sizes automatically.
Sizes of particular blocks may vary.
*/
VkDeviceSize blockSize;
/** \brief Minimum number of blocks to be always allocated in this pool, even if they stay empty.
Set to 0 to have no preallocated blocks and allow the pool be completely empty.
*/
size_t minBlockCount;
/** \brief Maximum number of blocks that can be allocated in this pool. Optional.
Set to 0 to use default, which is `SIZE_MAX`, which means no limit.
Set to same value as VmaPoolCreateInfo::minBlockCount to have fixed amount of memory allocated
throughout whole lifetime of this pool.
*/
size_t maxBlockCount;
/** \brief Maximum number of additional frames that are in use at the same time as current frame.
This value is used only when you make allocations with
#VMA_ALLOCATION_CREATE_CAN_BECOME_LOST_BIT flag. Such allocation cannot become
lost if allocation.lastUseFrameIndex >= allocator.currentFrameIndex - frameInUseCount.
For example, if you double-buffer your command buffers, so resources used for
rendering in previous frame may still be in use by the GPU at the moment you
allocate resources needed for the current frame, set this value to 1.
If you want to allow any allocations other than used in the current frame to
become lost, set this value to 0.
*/
uint32_t frameInUseCount;
} VmaPoolCreateInfo;
/** \brief Describes parameter of existing #VmaPool.
*/
typedef struct VmaPoolStats {
/** \brief Total amount of `VkDeviceMemory` allocated from Vulkan for this pool, in bytes.
*/
VkDeviceSize size;
/** \brief Total number of bytes in the pool not used by any #VmaAllocation.
*/
VkDeviceSize unusedSize;
/** \brief Number of #VmaAllocation objects created from this pool that were not destroyed or lost.
*/
size_t allocationCount;
/** \brief Number of continuous memory ranges in the pool not used by any #VmaAllocation.
*/
size_t unusedRangeCount;
/** \brief Size of the largest continuous free memory region available for new allocation.
Making a new allocation of that size is not guaranteed to succeed because of
possible additional margin required to respect alignment and buffer/image
granularity.
*/
VkDeviceSize unusedRangeSizeMax;
/** \brief Number of `VkDeviceMemory` blocks allocated for this pool.
*/
size_t blockCount;
} VmaPoolStats;
/** \brief Allocates Vulkan device memory and creates #VmaPool object.
@param allocator Allocator object.
@param pCreateInfo Parameters of pool to create.
@param[out] pPool Handle to created pool.
*/
VkResult vmaCreatePool(
VmaAllocator allocator,
const VmaPoolCreateInfo* pCreateInfo,
VmaPool* pPool);
/** \brief Destroys #VmaPool object and frees Vulkan device memory.
*/
void vmaDestroyPool(
VmaAllocator allocator,
VmaPool pool);
/** \brief Retrieves statistics of existing #VmaPool object.
@param allocator Allocator object.
@param pool Pool object.
@param[out] pPoolStats Statistics of specified pool.
*/
void vmaGetPoolStats(
VmaAllocator allocator,
VmaPool pool,
VmaPoolStats* pPoolStats);
/** \brief Marks all allocations in given pool as lost if they are not used in current frame or VmaPoolCreateInfo::frameInUseCount back from now.
@param allocator Allocator object.
@param pool Pool.
@param[out] pLostAllocationCount Number of allocations marked as lost. Optional - pass null if you don't need this information.
*/
void vmaMakePoolAllocationsLost(
VmaAllocator allocator,
VmaPool pool,
size_t* pLostAllocationCount);
/** \brief Checks magic number in margins around all allocations in given memory pool in search for corruptions.
Corruption detection is enabled only when `VMA_DEBUG_DETECT_CORRUPTION` macro is defined to nonzero,
`VMA_DEBUG_MARGIN` is defined to nonzero and the pool is created in memory type that is
`HOST_VISIBLE` and `HOST_COHERENT`. For more information, see [Corruption detection](@ref debugging_memory_usage_corruption_detection).
Possible return values:
- `VK_ERROR_FEATURE_NOT_PRESENT` - corruption detection is not enabled for specified pool.
- `VK_SUCCESS` - corruption detection has been performed and succeeded.
- `VK_ERROR_VALIDATION_FAILED_EXT` - corruption detection has been performed and found memory corruptions around one of the allocations.
`VMA_ASSERT` is also fired in that case.
- Other value: Error returned by Vulkan, e.g. memory mapping failure.
*/
VkResult vmaCheckPoolCorruption(VmaAllocator allocator, VmaPool pool);
/** \struct VmaAllocation
\brief Represents single memory allocation.
It may be either dedicated block of `VkDeviceMemory` or a specific region of a bigger block of this type
plus unique offset.
There are multiple ways to create such object.
You need to fill structure VmaAllocationCreateInfo.
For more information see [Choosing memory type](@ref choosing_memory_type).
Although the library provides convenience functions that create Vulkan buffer or image,
allocate memory for it and bind them together,
binding of the allocation to a buffer or an image is out of scope of the allocation itself.
Allocation object can exist without buffer/image bound,
binding can be done manually by the user, and destruction of it can be done
independently of destruction of the allocation.
The object also remembers its size and some other information.
To retrieve this information, use function vmaGetAllocationInfo() and inspect
returned structure VmaAllocationInfo.
Some kinds allocations can be in lost state.
For more information, see [Lost allocations](@ref lost_allocations).
*/
VK_DEFINE_HANDLE(VmaAllocation)
/** \brief Parameters of #VmaAllocation objects, that can be retrieved using function vmaGetAllocationInfo().
*/
typedef struct VmaAllocationInfo {
/** \brief Memory type index that this allocation was allocated from.
It never changes.
*/
uint32_t memoryType;
/** \brief Handle to Vulkan memory object.
Same memory object can be shared by multiple allocations.
It can change after call to vmaDefragment() if this allocation is passed to the function, or if allocation is lost.
If the allocation is lost, it is equal to `VK_NULL_HANDLE`.
*/
VkDeviceMemory deviceMemory;
/** \brief Offset into deviceMemory object to the beginning of this allocation, in bytes. (deviceMemory, offset) pair is unique to this allocation.
It can change after call to vmaDefragment() if this allocation is passed to the function, or if allocation is lost.
*/
VkDeviceSize offset;
/** \brief Size of this allocation, in bytes.
It never changes, unless allocation is lost.
*/
VkDeviceSize size;
/** \brief Pointer to the beginning of this allocation as mapped data.
If the allocation hasn't been mapped using vmaMapMemory() and hasn't been
created with #VMA_ALLOCATION_CREATE_MAPPED_BIT flag, this value null.
It can change after call to vmaMapMemory(), vmaUnmapMemory().
It can also change after call to vmaDefragment() if this allocation is passed to the function.
*/
void* pMappedData;
/** \brief Custom general-purpose pointer that was passed as VmaAllocationCreateInfo::pUserData or set using vmaSetAllocationUserData().
It can change after call to vmaSetAllocationUserData() for this allocation.
*/
void* pUserData;
} VmaAllocationInfo;
/** \brief General purpose memory allocation.
@param[out] pAllocation Handle to allocated memory.
@param[out] pAllocationInfo Optional. Information about allocated memory. It can be later fetched using function vmaGetAllocationInfo().
You should free the memory using vmaFreeMemory() or vmaFreeMemoryPages().
It is recommended to use vmaAllocateMemoryForBuffer(), vmaAllocateMemoryForImage(),
vmaCreateBuffer(), vmaCreateImage() instead whenever possible.
*/
VkResult vmaAllocateMemory(
VmaAllocator allocator,
const VkMemoryRequirements* pVkMemoryRequirements,
const VmaAllocationCreateInfo* pCreateInfo,
VmaAllocation* pAllocation,
VmaAllocationInfo* pAllocationInfo);
/** \brief General purpose memory allocation for multiple allocation objects at once.
@param allocator Allocator object.
@param pVkMemoryRequirements Memory requirements for each allocation.
@param pCreateInfo Creation parameters for each alloction.
@param allocationCount Number of allocations to make.
@param[out] pAllocations Pointer to array that will be filled with handles to created allocations.
@param[out] pAllocationInfo Optional. Pointer to array that will be filled with parameters of created allocations.
You should free the memory using vmaFreeMemory() or vmaFreeMemoryPages().
Word "pages" is just a suggestion to use this function to allocate pieces of memory needed for sparse binding.
It is just a general purpose allocation function able to make multiple allocations at once.
It may be internally optimized to be more efficient than calling vmaAllocateMemory() `allocationCount` times.
All allocations are made using same parameters. All of them are created out of the same memory pool and type.
If any allocation fails, all allocations already made within this function call are also freed, so that when
returned result is not `VK_SUCCESS`, `pAllocation` array is always entirely filled with `VK_NULL_HANDLE`.
*/
VkResult vmaAllocateMemoryPages(
VmaAllocator allocator,
const VkMemoryRequirements* pVkMemoryRequirements,
const VmaAllocationCreateInfo* pCreateInfo,
size_t allocationCount,
VmaAllocation* pAllocations,
VmaAllocationInfo* pAllocationInfo);
/**
@param[out] pAllocation Handle to allocated memory.
@param[out] pAllocationInfo Optional. Information about allocated memory. It can be later fetched using function vmaGetAllocationInfo().
You should free the memory using vmaFreeMemory().
*/
VkResult vmaAllocateMemoryForBuffer(
VmaAllocator allocator,
VkBuffer buffer,
const VmaAllocationCreateInfo* pCreateInfo,
VmaAllocation* pAllocation,
VmaAllocationInfo* pAllocationInfo);
/// Function similar to vmaAllocateMemoryForBuffer().
VkResult vmaAllocateMemoryForImage(
VmaAllocator allocator,
VkImage image,
const VmaAllocationCreateInfo* pCreateInfo,
VmaAllocation* pAllocation,
VmaAllocationInfo* pAllocationInfo);
/** \brief Frees memory previously allocated using vmaAllocateMemory(), vmaAllocateMemoryForBuffer(), or vmaAllocateMemoryForImage().
Passing `VK_NULL_HANDLE` as `allocation` is valid. Such function call is just skipped.
*/
void vmaFreeMemory(
VmaAllocator allocator,
VmaAllocation allocation);
/** \brief Frees memory and destroys multiple allocations.
Word "pages" is just a suggestion to use this function to free pieces of memory used for sparse binding.
It is just a general purpose function to free memory and destroy allocations made using e.g. vmaAllocateMemory(),
vmaAllocateMemoryPages() and other functions.
It may be internally optimized to be more efficient than calling vmaFreeMemory() `allocationCount` times.
Allocations in `pAllocations` array can come from any memory pools and types.
Passing `VK_NULL_HANDLE` as elements of `pAllocations` array is valid. Such entries are just skipped.
*/
void vmaFreeMemoryPages(
VmaAllocator allocator,
size_t allocationCount,
VmaAllocation* pAllocations);
/** \brief Tries to resize an allocation in place, if there is enough free memory after it.
Tries to change allocation's size without moving or reallocating it.
You can both shrink and grow allocation size.
When growing, it succeeds only when the allocation belongs to a memory block with enough
free space after it.
Returns `VK_SUCCESS` if allocation's size has been successfully changed.
Returns `VK_ERROR_OUT_OF_POOL_MEMORY` if allocation's size could not be changed.
After successful call to this function, VmaAllocationInfo::size of this allocation changes.
All other parameters stay the same: memory pool and type, alignment, offset, mapped pointer.
- Calling this function on allocation that is in lost state fails with result `VK_ERROR_VALIDATION_FAILED_EXT`.
- Calling this function with `newSize` same as current allocation size does nothing and returns `VK_SUCCESS`.
- Resizing dedicated allocations, as well as allocations created in pools that use linear
or buddy algorithm, is not supported.
The function returns `VK_ERROR_FEATURE_NOT_PRESENT` in such cases.
Support may be added in the future.
*/
VkResult vmaResizeAllocation(
VmaAllocator allocator,
VmaAllocation allocation,
VkDeviceSize newSize);
/** \brief Returns current information about specified allocation and atomically marks it as used in current frame.
Current paramters of given allocation are returned in `pAllocationInfo`.
This function also atomically "touches" allocation - marks it as used in current frame,
just like vmaTouchAllocation().
If the allocation is in lost state, `pAllocationInfo->deviceMemory == VK_NULL_HANDLE`.
Although this function uses atomics and doesn't lock any mutex, so it should be quite efficient,
you can avoid calling it too often.
- You can retrieve same VmaAllocationInfo structure while creating your resource, from function
vmaCreateBuffer(), vmaCreateImage(). You can remember it if you are sure parameters don't change
(e.g. due to defragmentation or allocation becoming lost).
- If you just want to check if allocation is not lost, vmaTouchAllocation() will work faster.
*/
void vmaGetAllocationInfo(
VmaAllocator allocator,
VmaAllocation allocation,
VmaAllocationInfo* pAllocationInfo);
/** \brief Returns `VK_TRUE` if allocation is not lost and atomically marks it as used in current frame.
If the allocation has been created with #VMA_ALLOCATION_CREATE_CAN_BECOME_LOST_BIT flag,
this function returns `VK_TRUE` if it's not in lost state, so it can still be used.
It then also atomically "touches" the allocation - marks it as used in current frame,
so that you can be sure it won't become lost in current frame or next `frameInUseCount` frames.
If the allocation is in lost state, the function returns `VK_FALSE`.
Memory of such allocation, as well as buffer or image bound to it, should not be used.
Lost allocation and the buffer/image still need to be destroyed.
If the allocation has been created without #VMA_ALLOCATION_CREATE_CAN_BECOME_LOST_BIT flag,
this function always returns `VK_TRUE`.
*/
VkBool32 vmaTouchAllocation(
VmaAllocator allocator,
VmaAllocation allocation);
/** \brief Sets pUserData in given allocation to new value.
If the allocation was created with VMA_ALLOCATION_CREATE_USER_DATA_COPY_STRING_BIT,
pUserData must be either null, or pointer to a null-terminated string. The function
makes local copy of the string and sets it as allocation's `pUserData`. String
passed as pUserData doesn't need to be valid for whole lifetime of the allocation -
you can free it after this call. String previously pointed by allocation's
pUserData is freed from memory.
If the flag was not used, the value of pointer `pUserData` is just copied to
allocation's `pUserData`. It is opaque, so you can use it however you want - e.g.
as a pointer, ordinal number or some handle to you own data.
*/
void vmaSetAllocationUserData(
VmaAllocator allocator,
VmaAllocation allocation,
void* pUserData);
/** \brief Creates new allocation that is in lost state from the beginning.
It can be useful if you need a dummy, non-null allocation.
You still need to destroy created object using vmaFreeMemory().
Returned allocation is not tied to any specific memory pool or memory type and
not bound to any image or buffer. It has size = 0. It cannot be turned into
a real, non-empty allocation.
*/
void vmaCreateLostAllocation(
VmaAllocator allocator,
VmaAllocation* pAllocation);
/** \brief Maps memory represented by given allocation and returns pointer to it.
Maps memory represented by given allocation to make it accessible to CPU code.
When succeeded, `*ppData` contains pointer to first byte of this memory.
If the allocation is part of bigger `VkDeviceMemory` block, the pointer is
correctly offseted to the beginning of region assigned to this particular
allocation.
Mapping is internally reference-counted and synchronized, so despite raw Vulkan
function `vkMapMemory()` cannot be used to map same block of `VkDeviceMemory`
multiple times simultaneously, it is safe to call this function on allocations
assigned to the same memory block. Actual Vulkan memory will be mapped on first
mapping and unmapped on last unmapping.
If the function succeeded, you must call vmaUnmapMemory() to unmap the
allocation when mapping is no longer needed or before freeing the allocation, at
the latest.
It also safe to call this function multiple times on the same allocation. You
must call vmaUnmapMemory() same number of times as you called vmaMapMemory().
It is also safe to call this function on allocation created with
#VMA_ALLOCATION_CREATE_MAPPED_BIT flag. Its memory stays mapped all the time.
You must still call vmaUnmapMemory() same number of times as you called
vmaMapMemory(). You must not call vmaUnmapMemory() additional time to free the
"0-th" mapping made automatically due to #VMA_ALLOCATION_CREATE_MAPPED_BIT flag.
This function fails when used on allocation made in memory type that is not
`HOST_VISIBLE`.
This function always fails when called for allocation that was created with
#VMA_ALLOCATION_CREATE_CAN_BECOME_LOST_BIT flag. Such allocations cannot be
mapped.
*/
VkResult vmaMapMemory(
VmaAllocator allocator,
VmaAllocation allocation,
void** ppData);
/** \brief Unmaps memory represented by given allocation, mapped previously using vmaMapMemory().
For details, see description of vmaMapMemory().
*/
void vmaUnmapMemory(
VmaAllocator allocator,
VmaAllocation allocation);
/** \brief Flushes memory of given allocation.
Calls `vkFlushMappedMemoryRanges()` for memory associated with given range of given allocation.
- `offset` must be relative to the beginning of allocation.
- `size` can be `VK_WHOLE_SIZE`. It means all memory from `offset` the the end of given allocation.
- `offset` and `size` don't have to be aligned.
They are internally rounded down/up to multiply of `nonCoherentAtomSize`.
- If `size` is 0, this call is ignored.
- If memory type that the `allocation` belongs to is not `HOST_VISIBLE` or it is `HOST_COHERENT`,
this call is ignored.
Warning! `offset` and `size` are relative to the contents of given `allocation`.
If you mean whole allocation, you can pass 0 and `VK_WHOLE_SIZE`, respectively.
Do not pass allocation's offset as `offset`!!!
*/
void vmaFlushAllocation(VmaAllocator allocator, VmaAllocation allocation, VkDeviceSize offset, VkDeviceSize size);
/** \brief Invalidates memory of given allocation.
Calls `vkInvalidateMappedMemoryRanges()` for memory associated with given range of given allocation.
- `offset` must be relative to the beginning of allocation.
- `size` can be `VK_WHOLE_SIZE`. It means all memory from `offset` the the end of given allocation.
- `offset` and `size` don't have to be aligned.
They are internally rounded down/up to multiply of `nonCoherentAtomSize`.
- If `size` is 0, this call is ignored.
- If memory type that the `allocation` belongs to is not `HOST_VISIBLE` or it is `HOST_COHERENT`,
this call is ignored.
Warning! `offset` and `size` are relative to the contents of given `allocation`.
If you mean whole allocation, you can pass 0 and `VK_WHOLE_SIZE`, respectively.
Do not pass allocation's offset as `offset`!!!
*/
void vmaInvalidateAllocation(VmaAllocator allocator, VmaAllocation allocation, VkDeviceSize offset, VkDeviceSize size);
/** \brief Checks magic number in margins around all allocations in given memory types (in both default and custom pools) in search for corruptions.
@param memoryTypeBits Bit mask, where each bit set means that a memory type with that index should be checked.
Corruption detection is enabled only when `VMA_DEBUG_DETECT_CORRUPTION` macro is defined to nonzero,
`VMA_DEBUG_MARGIN` is defined to nonzero and only for memory types that are
`HOST_VISIBLE` and `HOST_COHERENT`. For more information, see [Corruption detection](@ref debugging_memory_usage_corruption_detection).
Possible return values:
- `VK_ERROR_FEATURE_NOT_PRESENT` - corruption detection is not enabled for any of specified memory types.
- `VK_SUCCESS` - corruption detection has been performed and succeeded.
- `VK_ERROR_VALIDATION_FAILED_EXT` - corruption detection has been performed and found memory corruptions around one of the allocations.
`VMA_ASSERT` is also fired in that case.
- Other value: Error returned by Vulkan, e.g. memory mapping failure.
*/
VkResult vmaCheckCorruption(VmaAllocator allocator, uint32_t memoryTypeBits);
/** \struct VmaDefragmentationContext
\brief Represents Opaque object that represents started defragmentation process.
Fill structure #VmaDefragmentationInfo2 and call function vmaDefragmentationBegin() to create it.
Call function vmaDefragmentationEnd() to destroy it.
*/
VK_DEFINE_HANDLE(VmaDefragmentationContext)
/// Flags to be used in vmaDefragmentationBegin(). None at the moment. Reserved for future use.
typedef enum VmaDefragmentationFlagBits {
VMA_DEFRAGMENTATION_FLAG_BITS_MAX_ENUM = 0x7FFFFFFF
} VmaDefragmentationFlagBits;
typedef VkFlags VmaDefragmentationFlags;
/** \brief Parameters for defragmentation.
To be used with function vmaDefragmentationBegin().
*/
typedef struct VmaDefragmentationInfo2 {
/** \brief Reserved for future use. Should be 0.
*/
VmaDefragmentationFlags flags;
/** \brief Number of allocations in `pAllocations` array.
*/
uint32_t allocationCount;
/** \brief Pointer to array of allocations that can be defragmented.
The array should have `allocationCount` elements.
The array should not contain nulls.
Elements in the array should be unique - same allocation cannot occur twice.
It is safe to pass allocations that are in the lost state - they are ignored.
All allocations not present in this array are considered non-moveable during this defragmentation.
*/
VmaAllocation* pAllocations;
/** \brief Optional, output. Pointer to array that will be filled with information whether the allocation at certain index has been changed during defragmentation.
The array should have `allocationCount` elements.
You can pass null if you are not interested in this information.
*/
VkBool32* pAllocationsChanged;
/** \brief Numer of pools in `pPools` array.
*/
uint32_t poolCount;
/** \brief Either null or pointer to array of pools to be defragmented.
All the allocations in the specified pools can be moved during defragmentation
and there is no way to check if they were really moved as in `pAllocationsChanged`,
so you must query all the allocations in all these pools for new `VkDeviceMemory`
and offset using vmaGetAllocationInfo() if you might need to recreate buffers
and images bound to them.
The array should have `poolCount` elements.
The array should not contain nulls.
Elements in the array should be unique - same pool cannot occur twice.
Using this array is equivalent to specifying all allocations from the pools in `pAllocations`.
It might be more efficient.
*/
VmaPool* pPools;
/** \brief Maximum total numbers of bytes that can be copied while moving allocations to different places using transfers on CPU side, like `memcpy()`, `memmove()`.
`VK_WHOLE_SIZE` means no limit.
*/
VkDeviceSize maxCpuBytesToMove;
/** \brief Maximum number of allocations that can be moved to a different place using transfers on CPU side, like `memcpy()`, `memmove()`.
`UINT32_MAX` means no limit.
*/
uint32_t maxCpuAllocationsToMove;
/** \brief Maximum total numbers of bytes that can be copied while moving allocations to different places using transfers on GPU side, posted to `commandBuffer`.
`VK_WHOLE_SIZE` means no limit.
*/
VkDeviceSize maxGpuBytesToMove;
/** \brief Maximum number of allocations that can be moved to a different place using transfers on GPU side, posted to `commandBuffer`.
`UINT32_MAX` means no limit.
*/
uint32_t maxGpuAllocationsToMove;
/** \brief Optional. Command buffer where GPU copy commands will be posted.
If not null, it must be a valid command buffer handle that supports Transfer queue type.
It must be in the recording state and outside of a render pass instance.
You need to submit it and make sure it finished execution before calling vmaDefragmentationEnd().
Passing null means that only CPU defragmentation will be performed.
*/
VkCommandBuffer commandBuffer;
} VmaDefragmentationInfo2;
/** \brief Deprecated. Optional configuration parameters to be passed to function vmaDefragment().
\deprecated This is a part of the old interface. It is recommended to use structure #VmaDefragmentationInfo2 and function vmaDefragmentationBegin() instead.
*/
typedef struct VmaDefragmentationInfo {
/** \brief Maximum total numbers of bytes that can be copied while moving allocations to different places.
Default is `VK_WHOLE_SIZE`, which means no limit.
*/
VkDeviceSize maxBytesToMove;
/** \brief Maximum number of allocations that can be moved to different place.
Default is `UINT32_MAX`, which means no limit.
*/
uint32_t maxAllocationsToMove;
} VmaDefragmentationInfo;
/** \brief Statistics returned by function vmaDefragment(). */
typedef struct VmaDefragmentationStats {
/// Total number of bytes that have been copied while moving allocations to different places.
VkDeviceSize bytesMoved;
/// Total number of bytes that have been released to the system by freeing empty `VkDeviceMemory` objects.
VkDeviceSize bytesFreed;
/// Number of allocations that have been moved to different places.
uint32_t allocationsMoved;
/// Number of empty `VkDeviceMemory` objects that have been released to the system.
uint32_t deviceMemoryBlocksFreed;
} VmaDefragmentationStats;
/** \brief Begins defragmentation process.
@param allocator Allocator object.
@param pInfo Structure filled with parameters of defragmentation.
@param[out] pStats Optional. Statistics of defragmentation. You can pass null if you are not interested in this information.
@param[out] pContext Context object that must be passed to vmaDefragmentationEnd() to finish defragmentation.
@return `VK_SUCCESS` and `*pContext == null` if defragmentation finished within this function call. `VK_NOT_READY` and `*pContext != null` if defragmentation has been started and you need to call vmaDefragmentationEnd() to finish it. Negative value in case of error.
Use this function instead of old, deprecated vmaDefragment().
Warning! Between the call to vmaDefragmentationBegin() and vmaDefragmentationEnd():
- You should not use any of allocations passed as `pInfo->pAllocations` or
any allocations that belong to pools passed as `pInfo->pPools`,
including calling vmaGetAllocationInfo(), vmaTouchAllocation(), or access
their data.
- Some mutexes protecting internal data structures may be locked, so trying to
make or free any allocations, bind buffers or images, map memory, or launch
another simultaneous defragmentation in between may cause stall (when done on
another thread) or deadlock (when done on the same thread), unless you are
100% sure that defragmented allocations are in different pools.
- Information returned via `pStats` and `pInfo->pAllocationsChanged` are undefined.
They become valid after call to vmaDefragmentationEnd().
- If `pInfo->commandBuffer` is not null, you must submit that command buffer
and make sure it finished execution before calling vmaDefragmentationEnd().
For more information and important limitations regarding defragmentation, see documentation chapter:
[Defragmentation](@ref defragmentation).
*/
VkResult vmaDefragmentationBegin(
VmaAllocator allocator,
const VmaDefragmentationInfo2* pInfo,
VmaDefragmentationStats* pStats,
VmaDefragmentationContext *pContext);
/** \brief Ends defragmentation process.
Use this function to finish defragmentation started by vmaDefragmentationBegin().
It is safe to pass `context == null`. The function then does nothing.
*/
VkResult vmaDefragmentationEnd(
VmaAllocator allocator,
VmaDefragmentationContext context);
/** \brief Deprecated. Compacts memory by moving allocations.
@param pAllocations Array of allocations that can be moved during this compation.
@param allocationCount Number of elements in pAllocations and pAllocationsChanged arrays.
@param[out] pAllocationsChanged Array of boolean values that will indicate whether matching allocation in pAllocations array has been moved. This parameter is optional. Pass null if you don't need this information.
@param pDefragmentationInfo Configuration parameters. Optional - pass null to use default values.
@param[out] pDefragmentationStats Statistics returned by the function. Optional - pass null if you don't need this information.
@return `VK_SUCCESS` if completed, negative error code in case of error.
\deprecated This is a part of the old interface. It is recommended to use structure #VmaDefragmentationInfo2 and function vmaDefragmentationBegin() instead.
This function works by moving allocations to different places (different
`VkDeviceMemory` objects and/or different offsets) in order to optimize memory
usage. Only allocations that are in `pAllocations` array can be moved. All other
allocations are considered nonmovable in this call. Basic rules:
- Only allocations made in memory types that have
`VK_MEMORY_PROPERTY_HOST_VISIBLE_BIT` and `VK_MEMORY_PROPERTY_HOST_COHERENT_BIT`
flags can be compacted. You may pass other allocations but it makes no sense -
these will never be moved.
- Custom pools created with #VMA_POOL_CREATE_LINEAR_ALGORITHM_BIT or
#VMA_POOL_CREATE_BUDDY_ALGORITHM_BIT flag are not defragmented. Allocations
passed to this function that come from such pools are ignored.
- Allocations created with #VMA_ALLOCATION_CREATE_DEDICATED_MEMORY_BIT or
created as dedicated allocations for any other reason are also ignored.
- Both allocations made with or without #VMA_ALLOCATION_CREATE_MAPPED_BIT
flag can be compacted. If not persistently mapped, memory will be mapped
temporarily inside this function if needed.
- You must not pass same #VmaAllocation object multiple times in `pAllocations` array.
The function also frees empty `VkDeviceMemory` blocks.
Warning: This function may be time-consuming, so you shouldn't call it too often
(like after every resource creation/destruction).
You can call it on special occasions (like when reloading a game level or
when you just destroyed a lot of objects). Calling it every frame may be OK, but
you should measure that on your platform.
For more information, see [Defragmentation](@ref defragmentation) chapter.
*/
VkResult vmaDefragment(
VmaAllocator allocator,
VmaAllocation* pAllocations,
size_t allocationCount,
VkBool32* pAllocationsChanged,
const VmaDefragmentationInfo *pDefragmentationInfo,
VmaDefragmentationStats* pDefragmentationStats);
/** \brief Binds buffer to allocation.
Binds specified buffer to region of memory represented by specified allocation.
Gets `VkDeviceMemory` handle and offset from the allocation.
If you want to create a buffer, allocate memory for it and bind them together separately,
you should use this function for binding instead of standard `vkBindBufferMemory()`,
because it ensures proper synchronization so that when a `VkDeviceMemory` object is used by multiple
allocations, calls to `vkBind*Memory()` or `vkMapMemory()` won't happen from multiple threads simultaneously
(which is illegal in Vulkan).
It is recommended to use function vmaCreateBuffer() instead of this one.
*/
VkResult vmaBindBufferMemory(
VmaAllocator allocator,
VmaAllocation allocation,
VkBuffer buffer);
/** \brief Binds image to allocation.
Binds specified image to region of memory represented by specified allocation.
Gets `VkDeviceMemory` handle and offset from the allocation.
If you want to create an image, allocate memory for it and bind them together separately,
you should use this function for binding instead of standard `vkBindImageMemory()`,
because it ensures proper synchronization so that when a `VkDeviceMemory` object is used by multiple
allocations, calls to `vkBind*Memory()` or `vkMapMemory()` won't happen from multiple threads simultaneously
(which is illegal in Vulkan).
It is recommended to use function vmaCreateImage() instead of this one.
*/
VkResult vmaBindImageMemory(
VmaAllocator allocator,
VmaAllocation allocation,
VkImage image);
/**
@param[out] pBuffer Buffer that was created.
@param[out] pAllocation Allocation that was created.
@param[out] pAllocationInfo Optional. Information about allocated memory. It can be later fetched using function vmaGetAllocationInfo().
This function automatically:
-# Creates buffer.
-# Allocates appropriate memory for it.
-# Binds the buffer with the memory.
If any of these operations fail, buffer and allocation are not created,
returned value is negative error code, *pBuffer and *pAllocation are null.
If the function succeeded, you must destroy both buffer and allocation when you
no longer need them using either convenience function vmaDestroyBuffer() or
separately, using `vkDestroyBuffer()` and vmaFreeMemory().
If VMA_ALLOCATOR_CREATE_KHR_DEDICATED_ALLOCATION_BIT flag was used,
VK_KHR_dedicated_allocation extension is used internally to query driver whether
it requires or prefers the new buffer to have dedicated allocation. If yes,
and if dedicated allocation is possible (VmaAllocationCreateInfo::pool is null
and VMA_ALLOCATION_CREATE_NEVER_ALLOCATE_BIT is not used), it creates dedicated
allocation for this buffer, just like when using
VMA_ALLOCATION_CREATE_DEDICATED_MEMORY_BIT.
*/
VkResult vmaCreateBuffer(
VmaAllocator allocator,
const VkBufferCreateInfo* pBufferCreateInfo,
const VmaAllocationCreateInfo* pAllocationCreateInfo,
VkBuffer* pBuffer,
VmaAllocation* pAllocation,
VmaAllocationInfo* pAllocationInfo);
/** \brief Destroys Vulkan buffer and frees allocated memory.
This is just a convenience function equivalent to:
\code
vkDestroyBuffer(device, buffer, allocationCallbacks);
vmaFreeMemory(allocator, allocation);
\endcode
It it safe to pass null as buffer and/or allocation.
*/
void vmaDestroyBuffer(
VmaAllocator allocator,
VkBuffer buffer,
VmaAllocation allocation);
/// Function similar to vmaCreateBuffer().
VkResult vmaCreateImage(
VmaAllocator allocator,
const VkImageCreateInfo* pImageCreateInfo,
const VmaAllocationCreateInfo* pAllocationCreateInfo,
VkImage* pImage,
VmaAllocation* pAllocation,
VmaAllocationInfo* pAllocationInfo);
/** \brief Destroys Vulkan image and frees allocated memory.
This is just a convenience function equivalent to:
\code
vkDestroyImage(device, image, allocationCallbacks);
vmaFreeMemory(allocator, allocation);
\endcode
It it safe to pass null as image and/or allocation.
*/
void vmaDestroyImage(
VmaAllocator allocator,
VkImage image,
VmaAllocation allocation);
#ifdef __cplusplus
}
#endif
#endif // AMD_VULKAN_MEMORY_ALLOCATOR_H
// For Visual Studio IntelliSense.
#if defined(__cplusplus) && defined(__INTELLISENSE__)
#define VMA_IMPLEMENTATION
#endif
#ifdef VMA_IMPLEMENTATION
#undef VMA_IMPLEMENTATION
#include <cstdint>
#include <cstdlib>
#include <cstring>
/*******************************************************************************
CONFIGURATION SECTION
Define some of these macros before each #include of this header or change them
here if you need other then default behavior depending on your environment.
*/
/*
Define this macro to 1 to make the library fetch pointers to Vulkan functions
internally, like:
vulkanFunctions.vkAllocateMemory = &vkAllocateMemory;
Define to 0 if you are going to provide you own pointers to Vulkan functions via
VmaAllocatorCreateInfo::pVulkanFunctions.
*/
#if !defined(VMA_STATIC_VULKAN_FUNCTIONS) && !defined(VK_NO_PROTOTYPES)
#define VMA_STATIC_VULKAN_FUNCTIONS 1
#endif
// Define this macro to 1 to make the library use STL containers instead of its own implementation.
//#define VMA_USE_STL_CONTAINERS 1
/* Set this macro to 1 to make the library including and using STL containers:
std::pair, std::vector, std::list, std::unordered_map.
Set it to 0 or undefined to make the library using its own implementation of
the containers.
*/
#if VMA_USE_STL_CONTAINERS
#define VMA_USE_STL_VECTOR 1
#define VMA_USE_STL_UNORDERED_MAP 1
#define VMA_USE_STL_LIST 1
#endif
#ifndef VMA_USE_STL_SHARED_MUTEX
// Compiler conforms to C++17.
#if __cplusplus >= 201703L
#define VMA_USE_STL_SHARED_MUTEX 1
// Visual studio defines __cplusplus properly only when passed additional parameter: /Zc:__cplusplus
// Otherwise it's always 199711L, despite shared_mutex works since Visual Studio 2015 Update 2.
// See: https://blogs.msdn.microsoft.com/vcblog/2018/04/09/msvc-now-correctly-reports-__cplusplus/
#elif defined(_MSC_FULL_VER) && _MSC_FULL_VER >= 190023918 && __cplusplus == 199711L && _MSVC_LANG >= 201703L
#define VMA_USE_STL_SHARED_MUTEX 1
#else
#define VMA_USE_STL_SHARED_MUTEX 0
#endif
#endif
/*
THESE INCLUDES ARE NOT ENABLED BY DEFAULT.
Library has its own container implementation.
*/
#if VMA_USE_STL_VECTOR
#include <vector>
#endif
#if VMA_USE_STL_UNORDERED_MAP
#include <unordered_map>
#endif
#if VMA_USE_STL_LIST
#include <list>
#endif
/*
Following headers are used in this CONFIGURATION section only, so feel free to
remove them if not needed.
*/
#include <cassert> // for assert
#include <algorithm> // for min, max
#include <mutex>
#ifndef VMA_NULL
// Value used as null pointer. Define it to e.g.: nullptr, NULL, 0, (void*)0.
#define VMA_NULL nullptr
#endif
#if defined(__ANDROID_API__) && (__ANDROID_API__ < 16)
#include <cstdlib>
void *aligned_alloc(size_t alignment, size_t size)
{
// alignment must be >= sizeof(void*)
if(alignment < sizeof(void*))
{
alignment = sizeof(void*);
}
return memalign(alignment, size);
}
#elif defined(__APPLE__) || defined(__ANDROID__)
#include <cstdlib>
void *aligned_alloc(size_t alignment, size_t size)
{
// alignment must be >= sizeof(void*)
if(alignment < sizeof(void*))
{
alignment = sizeof(void*);
}
void *pointer;
if(posix_memalign(&pointer, alignment, size) == 0)
return pointer;
return VMA_NULL;
}
#endif
// If your compiler is not compatible with C++11 and definition of
// aligned_alloc() function is missing, uncommeting following line may help:
//#include <malloc.h>
// Normal assert to check for programmer's errors, especially in Debug configuration.
#ifndef VMA_ASSERT
#ifdef _DEBUG
#define VMA_ASSERT(expr) assert(expr)
#else
#define VMA_ASSERT(expr)
#endif
#endif
// Assert that will be called very often, like inside data structures e.g. operator[].
// Making it non-empty can make program slow.
#ifndef VMA_HEAVY_ASSERT
#ifdef _DEBUG
#define VMA_HEAVY_ASSERT(expr) //VMA_ASSERT(expr)
#else
#define VMA_HEAVY_ASSERT(expr)
#endif
#endif
#ifndef VMA_ALIGN_OF
#define VMA_ALIGN_OF(type) (__alignof(type))
#endif
#ifndef VMA_SYSTEM_ALIGNED_MALLOC
#if defined(_WIN32)
#define VMA_SYSTEM_ALIGNED_MALLOC(size, alignment) (_aligned_malloc((size), (alignment)))
#else
#define VMA_SYSTEM_ALIGNED_MALLOC(size, alignment) (aligned_alloc((alignment), (size) ))
#endif
#endif
#ifndef VMA_SYSTEM_FREE
#if defined(_WIN32)
#define VMA_SYSTEM_FREE(ptr) _aligned_free(ptr)
#else
#define VMA_SYSTEM_FREE(ptr) free(ptr)
#endif
#endif
#ifndef VMA_MIN
#define VMA_MIN(v1, v2) (std::min((v1), (v2)))
#endif
#ifndef VMA_MAX
#define VMA_MAX(v1, v2) (std::max((v1), (v2)))
#endif
#ifndef VMA_SWAP
#define VMA_SWAP(v1, v2) std::swap((v1), (v2))
#endif
#ifndef VMA_SORT
#define VMA_SORT(beg, end, cmp) std::sort(beg, end, cmp)
#endif
#ifndef VMA_DEBUG_LOG
#define VMA_DEBUG_LOG(format, ...)
/*
#define VMA_DEBUG_LOG(format, ...) do { \
printf(format, __VA_ARGS__); \
printf("\n"); \
} while(false)
*/
#endif
// Define this macro to 1 to enable functions: vmaBuildStatsString, vmaFreeStatsString.
#if VMA_STATS_STRING_ENABLED
static inline void VmaUint32ToStr(char* outStr, size_t strLen, uint32_t num)
{
snprintf(outStr, strLen, "%u", static_cast<unsigned int>(num));
}
static inline void VmaUint64ToStr(char* outStr, size_t strLen, uint64_t num)
{