Closed Bug 1484156 Opened 6 years ago Closed 6 years ago

Avoid crash on first run in about:performance

Categories

(Toolkit :: Performance Monitoring, enhancement)

Product:
Toolkit
Component:
Performance Monitoring
Type:
enhancement
Priority:
Not set
Severity:
normal

Tracking

()

Status:
RESOLVED FIXED
Tracking Flags:
Tracking Status
firefox64 --- wontfix

People

(Reporter: tarek, Assigned: florian)

References

Details

(Whiteboard: [perf-tools])

When users change the dom.performance.enable_scheduler_timing pref, the C++ internals don't see the change because it's a static pref and a restart is required. The about:performance UI OTHO thinks the pref is on and calls the performance counter, leading to this crash. We rely on a static pref because the scheduler calls the pref very early on when Firefox is started and we don't have yet gCacheData initialized so we crash here: https://searchfox.org/mozilla-central/source/modules/libpref/Preferences.cpp#5581 I don't know if we have a mechanism to detect that a static pref was changed and the browser not restarted, so maybe a pragmatic solution would be for the UI to detect that it's the first run, check that the pref was toggled, and ask the user for a restart.
Summary: Avoid crash on first run → Avoid crash on first run in about:performance
I am PTO starting this evening, and I don't think this crash is critical for now and can wait for Florian to get back so we can find the best solution with him. That said, if you want to prevent crashes in the two upcoming weeks, let me know, I can write today a patch that uses an ad-hoc mechanism to make sure the browser was restarted.
Flags: needinfo?(past)
I think this can wait. The pref is disabled by default and we have been communicating to the few people that are trying it out to restart after flipping the pref.
Flags: needinfo?(past)
Blocks: 1483934
Blocks: 1483873
This is a worksforme now that we flipped the pref, right?
Flags: needinfo?(florian)
Unless we want to keep it around until we fix bug 1498195, in case people keep flipping the pref for some reason.
The plan is to remove all the old code for 65. I don't think anybody plans to work on working around this for 64.
No longer blocks: new-about-performance-m1
status-firefox64: --- → wontfix
Flags: needinfo?(florian)

We removed the code of the old about:performance in bug 1498195 and bug 1406872.

Status: NEW → RESOLVED
Closed: 6 years ago
Resolution: --- → FIXED
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