A sheriff keeps an eye on the tree, DEPS rolls, Gold tool and the Perf tool.
Below is a brief summary of what the sheriff does for each task:
In general, sheriffs should have a strong bias towards actions that keep the tree green and then open; if a simple revert can fix the problem, the sheriff should revert first and ask questions later.
The list of sheriffs is specified in the skia-tree-status web app. The current sheriff is highlighted in green. The banner on the top of the status page also displays the current sheriff.
If you need to swap shifts with someone (because you are out sick or on vacation), please get approval from the person you want to swap with. Then send an email to skiabot@google.com to have someone make the database change (or directly ping rmistry@).
Pay close attention to the “Failures” view in the status page. Look at all existing BreakingTheBuildbots bugs. If the list is kept up to date then it should accurately represent everything that is causing failures. If it does not, then please file/update bugs accordingly.
A failure of the build steps in all compile bots automatically closes the tree. Sheriffs will have to manually reopen the tree manually when they deem the problem fixed.
Note: The tree is not closed automatically if the last run of the failed compile builder had the same failing step. The tree is also not closed if the tree was automatically closed less than 10 mins ago. If the tree is already closed then no action is taken.
See the revert documentation here.
A common cause of DEPS roll failures are layout tests. Find the offending Skia CL by examining the commit hash range in the DEPS roll and revert (or talk to the commit author if they are available). If you do revert then keep an eye on the next DEPS roll to make sure it succeeds.