1507827 - rusttest build changes lost sccache logging and stats

Status: NEW

(Firefox Build System :: General, enhancement)

Description

[(not currently active) Ted Mielczarek]

I didn't think about this while reviewing bug 1505072 but we launch the sccache server with logging from the `build::` target in client.mk:
https://dxr.mozilla.org/mozilla-central/rev/b0b856065d5b7ad2996f707e6e797d0d72afd803/client.mk#76-87

This means that changing the build targets that the rusttest builds use skip this step, so we don't get an sccache log out. I noticed this while looking at logs in bug 1507781.

In the guts of `mach build` we don't route through client.mk unless doing a no-argument build:
https://dxr.mozilla.org/mozilla-central/rev/b0b856065d5b7ad2996f707e6e797d0d72afd803/python/mozbuild/mozbuild/controller/building.py#1182

We do need to launch sccache via a Makefile so that it can inherit make's jobserver, but we could move that down into a special rule in the root Makefile and just call it from that build rule, and also invoke that special rule first in the rustttest builds.

Comment 1

[(not currently active) Ted Mielczarek]

https://treeherder.mozilla.org/#/jobs?repo=try&revision=a37366e331f47c99417e3935d919bab1de11c04e

Comment 2

[(not currently active) Ted Mielczarek]

Additionally we lost sccache stats on these jobs because the Makefile rules to dump sccache stats run on the default:: target:
https://dxr.mozilla.org/mozilla-central/rev/d6ac0dc85306b753c1d1d5f3084f73f0d1286b86/Makefile.in#206-212

Comment 3

[(not currently active) Ted Mielczarek]

https://treeherder.mozilla.org/#/jobs?repo=try&revision=b6bf963b3d70d41a36f6a3641073d1cc41d69c8e

Comment 4

[(not currently active) Ted Mielczarek]

(In reply to Ted Mielczarek [:ted] [:ted.mielczarek] from comment #3)
> https://treeherder.mozilla.org/#/
> jobs?repo=try&revision=b6bf963b3d70d41a36f6a3641073d1cc41d69c8e

That patch is a little ugly but it seems to fix both issues. I triggered a normal Linux build job as well just to be sure I didn't break things there and it looks OK.

We could certainly stand to make things nicer here. We could probably lift most of this logic up into `mach build` itself, just calling into a Makefile target to actually start sccache.

Comment 5

[Emma Humphries ☕️🎸🧞‍♀️✨ (she/they) [:emceeaich] (Pacific Time) use needinfo]

Per conversation with :kmoir, I'm going through untriaged bugs in her components and marking the ones which look to be enhancements/tasks with the enhancement severity to get them out of the triage queue.

If this incorrect, please remove the tag.