1586508 - suite/-only pushes cause builds without test runs, and other pushes do too

Status: RESOLVED WORKSFORME

(Thunderbird :: Build Config, defect)

Description

[Jorg K (CEST = GMT+2)]

suite/ only pushes cause builds without test runs, for example here:
https://treeherder.mozilla.org/#/jobs?repo=comm-central&revision=f5938d7c1eca1cbfab51c9ae963ecf1e71d17824

Pushes that only modify "unimportant" files cause Dailies not to run tests, for example here:
https://treeherder.mozilla.org/#/jobs?repo=comm-central&revision=81233eef62edcad1e1f548e2165c33960070e3e2
https://treeherder.mozilla.org/#/jobs?repo=comm-central&revision=a560168b6ca58f8daf34236f20d979bdf09786a1

All that leads to unexpected behaviour an ultimately wastes resources. Desired behaviour:

• suite/-only should not cause any builds
• Nightlies based on whichever changes should always run tests.

Comment 1

[Rob Lemley [:rjl]]

Hmm.. not entirely sure why those Suite-only builds happened.

Ideally, the when.files-changed would apply all of the time, but obviously there is something that's overriding that. The full task graph gets generated regardless, then if none of the files in that push match up with files-changed, the build job should get optimized away. As that's not the case, I believe one of two things is happening:

1. There is a task that depends on the build task that for some reason is not being optimized out
2. There is an override someplace when a build is set "shippable" that prevents optimizing

I suspect #1 is the culprit, but I wasn't able to figure out which dependent task is not being optimized out. It's odd though that the tests get optimized out but the build isn't.

I'm thinking I may need to come up with a custom optimization strategy rather than trying to mangle the existing Firefox ones into our workflow. That's probably easier said that done given how the code is structured, but it's time to figure out how to start doing things like this.

More to come.

Comment 2

[Rob Lemley [:rjl]]

I think this was addressed by another similar bug (maybe 1550611). Marking resolved, can reopen if needed.