1631402 - remove code in pickle.cc recording start/end timestamps purely for probes that have expired

Status: RESOLVED FIXED

(Core :: IPC, task, P5)

Description

[:Gijs (he/him)]

https://searchfox.org/mozilla-central/rev/a4d62e09a4c46aef918667fa759bf9ae898dc258/toolkit/components/telemetry/Histograms.json#13442-13464

These expired in version 60, but the code is still there, and can be expensive - in https://perfht.ml/2Vqjbal (which is a debug build), the resulting calls to RtlQueryPerformanceCounter top the list of where the worker is spending time - and this is on top of the fact that it's a worker so the probe presumably doesn't care about the data from there, only for the main thread (filtering for which happens only after recording the start time, https://searchfox.org/mozilla-central/rev/a4d62e09a4c46aef918667fa759bf9ae898dc258/ipc/chromium/src/base/pickle.cc#460-469 ).

Comment 1

[BugBot [:suhaib / :marco/ :calixte]]

The priority flag is not set for this bug.
:jld, could you have a look please?

For more information, please visit auto_nag documentation.

Comment 2

[Nika Layzell [:nika] (ni? for response)]

Attachment: Bug 1631402 - Remove expired IPC_MAIN_THREAD_LATENCY probes, r=#ipc-reviewers

Comment 3

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/686ae9e71a9c
Remove expired IPC_MAIN_THREAD_LATENCY probes, r=ipc-reviewers,mccr8

Comment 4

[Noemi Erli[:noemi_erli]]

Backed out changeset 686ae9e71a9c (Bug 1631402) for causing build bustage in MessageChannel.cpp

Push with failures: https://treeherder.mozilla.org/jobs?repo=autoland&selectedTaskRun=BJ1hG_M8QvKg9dbnZXCVDg.0&resultStatus=testfailed%2Cbusted%2Cexception%2Cretry%2Cusercancel&revision=686ae9e71a9c6d73c363dee78b03de4359f2e27a

Log: https://treeherder.mozilla.org/logviewer?job_id=363167583&repo=autoland&lineNumber=41001

Backout: https://hg.mozilla.org/integration/autoland/rev/e124bef8ffab130f5db09c9cbb4c00cf6a477aa4

Comment 5

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/70ef1676998c
Remove expired IPC_MAIN_THREAD_LATENCY probes, r=ipc-reviewers,mccr8

Comment 6

[Alexandru Michis [:malexandru]]

https://hg.mozilla.org/mozilla-central/rev/70ef1676998c