Bug 219053

Summary: Make sure ProcessThrottler is always holding a ProcessAssertion for its child process
Product: WebKit Reporter: Chris Dumez <cdumez>
Component: WebKit2Assignee: Chris Dumez <cdumez>
Status: RESOLVED FIXED    
Severity: Normal CC: ggaren, webkit-bug-importer
Priority: P2 Keywords: InRadar
Version: WebKit Nightly Build   
Hardware: Unspecified   
OS: Unspecified   
Attachments:
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Description Chris Dumez 2020-11-17 14:37:50 PST
Make sure ProcessThrottler is always holding a ProcessAssertion for its child process. Previously, when changing the assertion type (e.g. when going from background to foreground) we would release the previous assertion and then take the new one.
RunningBoard developers recommend that we wait until the new ProcessAssertion is taken before we release the previous one to avoid churn. It is also important we always hold a ProcessAssertion at all times for the child process because the child process may exit otherwise.
Comment 1 Chris Dumez 2020-11-17 14:39:18 PST
Created attachment 414386 [details]
Patch
Comment 2 Geoffrey Garen 2020-11-17 14:58:25 PST
Comment on attachment 414386 [details]
Patch

View in context: https://bugs.webkit.org/attachment.cgi?id=414386&action=review

r=me

> Source/WebKit/UIProcess/ProcessThrottler.cpp:132
> +    // Keep the previous assertion around until after the new one has been created so that we always have
> +    // hold a process assertion for the process.

have hold => hold
Comment 3 Chris Dumez 2020-11-17 15:00:53 PST
Created attachment 414388 [details]
Patch
Comment 4 EWS 2020-11-17 16:36:33 PST
Committed r269934: <https://trac.webkit.org/changeset/269934>

All reviewed patches have been landed. Closing bug and clearing flags on attachment 414388 [details].
Comment 5 Radar WebKit Bug Importer 2020-11-17 16:37:20 PST
<rdar://problem/71512123>