Closed Bug 1482240 Opened 6 years ago Closed 3 years ago

[meta] ThreadResponsiveness uses nsITimer in a way which may disturb idleness checks

Categories

(Core :: Gecko Profiler, enhancement, P3)

Product:
Core
Component:
Gecko Profiler
Type:
enhancement

Tracking

()

Status:
RESOLVED WORKSFORME

People

(Reporter: smaug, Unassigned)

References

(Blocks 1 open bug)

Details

(Keywords: meta)

ThreadResponsiveness uses TYPE_ONE_SHOT timers. If such timer is about to run, idle runnables won't be processed. *_LOW_PRIORITY timer might be better here https://searchfox.org/mozilla-central/rev/0f4d50ff5211e8dd85e119ef683d04b63062ed90/xpcom/threads/nsITimer.idl#127-134 since that way profiler code would affect less how browser works. It is still unclear to me what the number for "event processing delay" would mean in that case though. If there is idle time detected, it is perfectly ok to run something a bit longer.
Bug 1482244 is another way to approach this - it'll mean that we won't need to dispatch any runnables / timers at all in order to measure responsiveness.
Blocks: 1329212
Priority: -- → P3

I think we should tackle this in some way, either using different type of timer or the way bug 1482244 approaches the issue. We rely on idle queue when dealing with timers and also refresh driver uses idle queue occasionally (with timeout value). If raptor/tp6 profiles page loads with "Responsiveness" set on, it may not give accurate results.

Whiteboard: [qf]

rwood told that raptor/tp6 is profiled only once a day.

Whiteboard: [qf] → [qf:meta]
Depends on: 1543147

Mass-removing myself from cc; search for 12b9dfe4-ece3-40dc-8d23-60e179f64ac1 or any reasonable part thereof, to mass-delete these notifications (and sorry!)

Performance Impact: --- → ?
Keywords: meta
Whiteboard: [qf:meta]
Summary: ThreadResponsiveness uses nsITimer in a way which may disturb idleness checks → [meta] ThreadResponsiveness uses nsITimer in a way which may disturb idleness checks
Performance Impact: ? → ---

smaug: The only dependency for this meta bug was closed as WONTFIX. Do we need to keep this open?

Flags: needinfo?(bugs)

I think this is indeed fixed now.

Status: NEW → RESOLVED
Closed: 3 years ago
Flags: needinfo?(bugs)
Resolution: --- → WORKSFORME
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