1615727 - Enable base profiler for startup Talos tests

Status: RESOLVED DUPLICATE of bug 1586939

(Testing :: Talos, task, P3)

Description

[Mike Conley (:mconley) (:⚙️)]

The base profiler work in bug 1492121 makes it possible to get samples from before XPCOM starts up. This is useful data to have for things like startup performance.

So we should enable the base profiler for our startup performance tests.

Comment 1

[Mike Conley (:mconley) (:⚙️)]

Attachment: Bug 1615727 - Enable base profiler when profiling Talos startup tests. r?davehunt

Comment 2

[Florian Quèze [:florian]]

Marking fxperf:p1 because there's already a patch, but given bug 1586939 should (hopefully soon) remove the need for this patch, I would otherwise have given this a lower priority.

Comment 3

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/7dee76ec48c4
Enable base profiler when profiling Talos startup tests. r=davehunt

Comment 4

[Natalia Csoregi [:nataliaCs]]

https://hg.mozilla.org/mozilla-central/rev/7dee76ec48c4

Comment 5

[Mike Conley (:mconley) (:⚙️)]

This appears to have contributed to bug 1220362.

Hey malexandru, would you be able to back out 7dee76ec48c4 when you have a moment?

Comment 6

[Alexandru Michis [:malexandru]]

Done, thank you!

Comment 7

[Pulsebot]

Backout by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/5490c9f430b8
Backed out changeset 7dee76ec48c4 for causing Talos failures.

Comment 8

[Sebastian Hengst [:aryx] (needinfo me if it's about an intermittent or backout)]

Backout merged: https://hg.mozilla.org/mozilla-central/rev/5490c9f430b8

Comment 9

[Henrik Skupin [:whimboo][⌚️UTC+1]]

Hey Mike, I assume we still want that? Are you going to continue working on the bug?

Comment 10

[Henrik Skupin [:whimboo][⌚️UTC+1]]

Maybe we should simply wait for bug 1586939 to be fixed?

Comment 11

[Henrik Skupin [:whimboo][⌚️UTC+1]]

(In reply to Henrik Skupin (:whimboo) [⌚️UTC+2] from comment #10)

Maybe we should simply wait for bug 1586939 to be fixed?

Gerald, maybe you can add some feedback here? Given that you know more about the ETA here. I'm fairly sure it can still wait for a moment.

Comment 12

[Gerald Squelart (he/him) (not at Mozilla since 2022-09-15)]

Alright, I'll start tomorrow! Sorry for the delay.

Comment 13

[Henrik Skupin [:whimboo][⌚️UTC+1]]

Thanks. I assume we can mark it as dependent then.

Comment 14

[Henrik Skupin [:whimboo][⌚️UTC+1]]

Gerald, is there anything else we would have to do for Talos, or shall we dupe this bug to bug 1586939?

Comment 15

[Gerald Squelart (he/him) (not at Mozilla since 2022-09-15)]

Henrik: Now that bug 1586939 has landed, Base Profiler should Just Work™!

I don't know how the profiler is activated in these tests. If you set the environment variable MOZ_PROFILER_STARTUP=1 before starting Firefox, the output profile should contain new tracks named "GeckoMain (pre-xul)" with profiling information from before the main Gecko Profiler start in XUL. E.g.: https://share.firefox.dev/36NLPpK

To calibrate expectations: At the moment it's only the main thread, and there are no markers and few labels, so you'll only see stack sampling during that time. Markers&labels could be added outside of XUL, through "BaseProfiler.h" functions.

Comment 16

[Henrik Skupin [:whimboo][⌚️UTC+1]]

Yes, I can see those tracks in the appropriate Talos jobs now that are related to profiling the startup. Here one example for the startup about:home paint:

https://treeherder.mozilla.org/#/jobs?repo=mozilla-central&tier=1%2C2%2C3&searchStr=talos%2Cprof&selectedTaskRun=AZLuBbpaRw6Qo029sK09Bg-0

Profile: https://share.firefox.dev/3cpxW2c

Mike or Florian, I assume that looks all fine now and we can close this bug as fixed?

Comment 17

[Florian Quèze [:florian]]

Yes, looks good to me now! Thanks for checking the profiles :-).