Closed Bug 1586357 Opened 10 months ago Closed 10 months ago

Only force re-linking on 1-tier PGO builds

Categories

(Firefox Build System :: General, defect)

defect
Not set
normal

Tracking

(firefox71 fixed)

RESOLVED FIXED
mozilla71
Tracking Status
firefox71 --- fixed

People

(Reporter: mshal, Assigned: mshal)

Details

Attachments

(1 file)

Local PGO builds (MOZ_PGO=1 ./mach build) still use 1-tier machinery until bug 1563403 is fixed. However, that doesn't stop someone from doing a 3-tier PGO build by fiddling with --enable-profile-generate/use flags and running the profile server. If they do, MOZ_AUTOMATION isn't set, which means buildsymbols recurses through the tree:

https://searchfox.org/mozilla-central/rev/2f29d53865cb895bf16c91336cc575aecd996a17/Makefile.in#242

Unfortunately 1-tier PGO uses a FORCE rule to force re-linking libraries & binaries in the profile-use stage, defined here:

https://searchfox.org/mozilla-central/rev/2f29d53865cb895bf16c91336cc575aecd996a17/config/rules.mk#478

So a subsequent buildsymbols will recurse through the tree, then forcefully re-link everything, which can add quite a bit of time to the build. Until bug 1563403 removes the rest of the 1-tier PGO stuff, we can hide the FORCE rule behind the MOZ_1TIER_PGO flag so it doesn't impact a local 3-tier PGO build.

Pushed by mshal@mozilla.com:
https://hg.mozilla.org/integration/autoland/rev/70367c5e41fc
Only force re-linking on 1-tier PGO builds; r=firefox-build-system-reviewers,chmanchester
Status: NEW → RESOLVED
Closed: 10 months ago
Resolution: --- → FIXED
Target Milestone: --- → mozilla71
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