tree 0e0d66565db83ba4821f95bed4b12c11fbb804f3
parent 3c0864132f49063be6ae7225e3d754cf33654814
author Jonathan Lee <jonathanjlee@google.com> 1748392022 -0700
committer Chromium LUCI CQ <chromium-scoped@luci-project-accounts.iam.gserviceaccount.com> 1748392022 -0700

[wptrunner] Log each event's thread name on the bots

To diagnose bugs like https://crbug.com/417806060, the bots will now run
with verbosity level 1, which installs a modified `mach` formatter with
thread names logged. This will establish what sequence of tests each
worker ran (identified as `TestRunnerManager-<N>`).

Also, tweak and document what the other log levels do.
`run_wpt_tests.py` at verbosity 0 has no change (i.e., still uses the
`grouping` formatter).

Bug: None
Test: Spot-check swarming logs
Change-Id: I6e84b48eb55987cf6bfc4a5d5cabf0af4884597b
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/6581659
Commit-Queue: Jonathan Lee <jonathanjlee@google.com>
Reviewed-by: Weizhong Xia <weizhong@google.com>
Reviewed-by: Thomas Anderson <thomasanderson@chromium.org>
Reviewed-by: Zhaoyang Li <zhaoyangli@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1466234}