1838306 - Look into making CaR builds uncached

Status: RESOLVED FIXED

(Testing :: Raptor, enhancement, P3)

Description

[Kash Shampur [:kshampur] ⌚EST]

Currently in cron, we schedule the CaR to be built daily [1] [2], before the scheduled CaR tests [3]

This current sequence of tasks relies on the build toolchain successfully passing and being available in $moz_fetches_dir ahead of the scheduled tasks. So far this hasnt been an issue.

However since we only use CaR for performance tests, it could be worth looking into making CaR builds unchached builds (e.g. [4] & [5])

That way the CaR build happens when the related perftests are scheduled

(TBD)
a potential downside is if someone were to run it on a Try push, each separate push would trigger a new build rather than using the existing build from the previous push, if within a short time span. (which could be okay for win/linux which are relatively shorter builds, but mac takes a long time, also maybe that's fine since this may not be a typical use-case for CaR down the line).

(We even look into doing the same with the chromium fetches?)

Comment 1

[Kash Shampur [:kshampur] ⌚EST]

This currently happens now.
e.g. https://searchfox.org/mozilla-central/rev/ee2ad260c25310a9fbf96031de05bbc0e94394cc/taskcluster/kinds/toolchain/misc.yml#207
and the CaR builds are triggered by the CaR tasks

un caching was first introduced in Bug 1868998
Bug 1867068 improved on the task scheduling a bit

the chromium fetch was also improved in Bug 1890666