1948387 - Use arm emulator for Fenix arm32 PGO

Status: RESOLVED FIXED

(Core :: Performance Engineering, enhancement)

Description

[Ted Campbell [:tcampbell]]

This follows in the same spirit as Bug 1865886, but for 32-bit ARM. In unrelated investigations I found that the system-images;android-30;google_apis;x86 is the equivalent for ARM32 as we found android-31 was for arm64 (https://bugzilla.mozilla.org/show_bug.cgi?id=1865886#c4).

Updating the arm32 pgo process to be aligned with the arm64 process I seem to be able to get working builds without any fuss. The Bpgo(run) task thus uses libndk_translation.so on x86 Android emulator on linux64 host. The result is still that we have appropriate PGO for arm-specific code paths (JITs, media, crypto, etc).

Using these builds on a physical Pixel 3 (that is 64-bit capable), I see a consistent 11% performance improvement on Speedometer 3 on Fenix Nightly Simulation builds.

Baseline: https://treeherder.mozilla.org/jobs?repo=try&selectedTaskRun=fKIQkf0kRhqtr413LgvLSw.0&revision=8764b78e04734257fdc2d3223130785bd1324956
Arm32-PGO: https://treeherder.mozilla.org/jobs?repo=try&selectedTaskRun=GVMBG3WIS7ue4O5UJ8QYBg.0&revision=a498ece3c67436a3bba068cf75fc47fdd7e46710

Comment 1

[Ted Campbell [:tcampbell]]

Attachment: Bug 1948387 - Run android arm pgo on arm-on-x86 android-30 emulator

Bring the ARM32 PGO builds in line with ARM64 PGO by also running them on an
emulator with translation support. Previously we used the x86 profile data.

Comment 2

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/a415debf8272
Run android arm pgo on arm-on-x86 android-30 emulator r=glandium,releng-reviewers,bhearsum

Comment 3

[Sandor Molnar[:smolnar]]

https://hg.mozilla.org/mozilla-central/rev/a415debf8272