| // Package tracing consolidates the setup logic for using opencensus tracing and exporting the |
| // metrics. It is based off of //perf/go/tracing/ |
| package tracing |
| |
| import ( |
| "os" |
| "time" |
| |
| "contrib.go.opencensus.io/exporter/stackdriver" |
| "go.opencensus.io/trace" |
| "go.skia.org/infra/go/skerr" |
| ) |
| |
| // Initialize sets up trace options and exporting for this application. It will sample the given |
| // proportion of traces. |
| func Initialize(traceSampleProportion float64) error { |
| exporter, err := stackdriver.NewExporter(stackdriver.Options{ |
| // Use 10 times the default (because that's what perf does). |
| TraceSpansBufferMaxBytes: 80_000_000, |
| // It is not clear what the default interval is. One minute seems to be a good value since |
| // that is the same as our Prometheus metrics are reported. |
| ReportingInterval: time.Minute, |
| DefaultTraceAttributes: map[string]interface{}{ |
| // This environment variable should be set in the k8s templates. |
| "podName": os.Getenv("K8S_POD_NAME"), |
| }, |
| }) |
| if err != nil { |
| return skerr.Wrap(err) |
| } |
| |
| trace.RegisterExporter(exporter) |
| sampler := trace.ProbabilitySampler(traceSampleProportion) |
| trace.ApplyConfig(trace.Config{DefaultSampler: sampler}) |
| return nil |
| } |