Bug 209825

Summary: [iOS] Replace UIKit background task with a RunningBoard FinishTaskInterruptable assertion
Product: WebKit Reporter: Chris Dumez <cdumez>
Component: WebKit2Assignee: Chris Dumez <cdumez>
Status: RESOLVED FIXED    
Severity: Normal CC: achristensen, beidson, benjamin, cmarcelo, darin, ews-watchlist, ggaren, jer.noble, webkit-bug-importer
Priority: P2 Keywords: InRadar
Version: WebKit Nightly Build   
Hardware: Unspecified   
OS: Unspecified   
Bug Depends on:    
Bug Blocks: 209990    
Attachments:
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Description Chris Dumez 2020-03-31 11:59:25 PDT 
Replace UIKit background task with a RunningBoard FinishTask assertion on iOS. Our UIProcess gets terminated too frequently when the UIKit background task expires when the UIProcess holds it for longer than 30 seconds in the background. The RunningBoard FinishTask assertion is supposed to be equivalent but would cause suspension of our UIProcess on expiration, instead of termination.
Comment 1 Radar WebKit Bug Importer 2020-03-31 11:59:39 PDT 
<rdar://problem/61118503>
Comment 2 Chris Dumez 2020-03-31 12:21:47 PDT 
Created attachment 395077 [details]
Patch
Comment 3 Chris Dumez 2020-03-31 14:07:20 PDT 
Looks like I need to fix up the open source build. Will look into it shortly.
Comment 4 Chris Dumez 2020-03-31 14:57:24 PDT 
Created attachment 395095 [details]
Patch
Comment 5 Chris Dumez 2020-03-31 15:25:22 PDT 
Created attachment 395098 [details]
Patch
Comment 6 Darin Adler 2020-03-31 16:30:20 PDT 
Comment on attachment 395098 [details]
Patch

View in context: https://bugs.webkit.org/attachment.cgi?id=395098&action=review

> Source/WTF/wtf/PlatformHave.h:461
> +#if PLATFORM(IOS_FAMILY) && __IPHONE_OS_VERSION_MIN_REQUIRED >= 140000
> +#define HAVE_RUNNINGBOARD_WEBKIT_ASSERTIONS 1
> +#endif

This doesn’t work as you’d expect. It‘s the thing Tim has been reminding us about. IOS_FAMILY plus __IPHONE_OS_VERSION_MIN_REQUIRED >= 140000 gives iOS *without* watchOS and tvOS.
Comment 7 Chris Dumez 2020-03-31 17:15:06 PDT 
(In reply to Darin Adler from comment #6)
> Comment on attachment 395098 [details]
> Patch
> 
> View in context:
> https://bugs.webkit.org/attachment.cgi?id=395098&action=review
> 
> > Source/WTF/wtf/PlatformHave.h:461
> > +#if PLATFORM(IOS_FAMILY) && __IPHONE_OS_VERSION_MIN_REQUIRED >= 140000
> > +#define HAVE_RUNNINGBOARD_WEBKIT_ASSERTIONS 1
> > +#endif
> 
> This doesn’t work as you’d expect. It‘s the thing Tim has been reminding us
> about. IOS_FAMILY plus __IPHONE_OS_VERSION_MIN_REQUIRED >= 140000 gives iOS
> *without* watchOS and tvOS.

I had copied an existing example in our code hoping bad things in the code base had been fixed.
Comment 8 Chris Dumez 2020-03-31 17:15:24 PDT 
Created attachment 395109 [details]
Patch
Comment 9 Chris Dumez 2020-04-02 09:10:28 PDT 
Ping review?
Comment 10 Geoffrey Garen 2020-04-02 13:22:45 PDT 
Comment on attachment 395109 [details]
Patch

r=me
Comment 11 EWS 2020-04-02 13:49:09 PDT 
Committed r259414: <https://trac.webkit.org/changeset/259414>

All reviewed patches have been landed. Closing bug and clearing flags on attachment 395109 [details].