Sheriffed intermittent failures =============================== The Firefox Sheriff team looks at all failures for tasks which are visible by default in Treeherder (tier 1 and 2) and are part of a push on a sheriffed tree (autoland, mozilla-central, mozilla-beta, mozilla-release, mozilla-esr trees) and determines if the failure is a regression or an intermittent failure. In the case of an intermittent failure, the sheriffs annotate the failure and the annotation is logged in [Treeherder](https://treeherder.mozilla.org/intermittent-failures). In most cases the sheriffs will determine if a new bug is needed or an existing bug already tracks this kind of failure. In most cases sheriffs will annotate the failure using a "Single Tracking Bug", in other cases there will be specific failures that are tracked seperately. Single tracking bugs -------------------- Single tracking bugs are used to track test failures seen in CI. These are tracked at the test case level (typically path/filename) instead of the error message. We have found that many times we have >1 bug tracking failures on a test case, but none of the bugs are frequent enough to get attention of the test owners. In addition, when a developer is looking into fixing an intermittent failure, they are debugging the file, and it is great to see ALL the related failures in one place. There are 2 ways to get detailed information about test failures: 1. [Treeherder](https://treeherder.mozilla.org/intermittent-failures), when viewing a specific issue, there is a table, on the far right side of the table is the column titled `Log`. If you click the text box underneath that, a drop down of all failure types will be populated, selecting a failure will filter on that failure to see logs, etc. 2. from `mach test-info`, one can view a breakdown of all failures and where they occur (example: `./mach test-info failure-report --bugid 1781668`) The workflow of single tracking bugs is as follows: - Sheriffs find new failures in CI and create new bugs. If Treeherder can find the path, Treeherder will recommend a `single tracking bug` and strip out the error message. - Sheriffs will annotate existing bugs if the failure to annotate has a test path and in the list of bug suggestions there is a `single tracking bug`. Treeherder will offer that up as the choice as long as the test paths match (and other criteria like crashes, assertions, leaks, etc. are met) - Sheriffs will needinfo triage owner if enough failures occur (currently 30 failures a week, etc.) - Developers will be able to investigate the set of failures, any specific bugs they are fixing (for some or all of the conditions). It is best practice to use the `single tracking bug` as a META bug and file a new bug blocking the META bug with the specific fix.