Bug 102585

Summary: Performance degradation while rendering MathML content, freezes the tab.
Product: WebKit Reporter: A George <ancil0504>
Component: MathMLAssignee: Tony Chang <tony>
Status: RESOLVED FIXED    
Severity: Critical CC: cgarcia, davidc, dbarton, eric, fred.wang, ojan, tony, webkit.review.bot
Priority: P1    
Version: 528+ (Nightly build)   
Hardware: PC   
OS: Windows 7   
Bug Depends on: 102352    
Bug Blocks:    
Attachments:
Description Flags
Test Page 1
none
Test Page 2
none
Patch none

A George
Reported 2012-11-17 00:28:03 PST
Created attachment 174814 [details] Test Page 1 There is a performance degradation on latest Chrome Canary builds and Webkit Nightly builds(WebKit-r131444) while rendering MathML content. Verified on older nightly builds and found that after change set r128837 (Mathml to use flexboxes) the issue is seen. Findings below WebKit-r128813: Test page 1 & 2 works well on WinLauncher and Webkit.exe WebKit-r128857/WebKit-r131444: Test page 1 - Renders after a perceivable delay in WinLauncher and Webkit.exe Test page 2 - Both Winlauncher & Webkit.exe freezes/hangs Chrome Canary Version 25.0.1326.0 canary: Test page 1 - Renders after a perceivable delay. Test page 2 - Application freezes/hangs and after sometime shows 'Page unresponsive' pop-up.
Attachments
Test Page 1 (903 bytes, text/html)
2012-11-17 00:28 PST, A George 		no flags
Details
Test Page 2 (1.21 KB, text/html)
2012-11-17 00:28 PST, A George 		no flags
Details
Patch (2.53 KB, patch)
2012-12-03 11:13 PST, Tony Chang 		no flags
DetailsFormatted DiffDiff
View All Add attachment proposed patch, testcase, etc.
A George
Comment 1 2012-11-17 00:28:34 PST
Created attachment 174815 [details] Test Page 2
Tony Chang
Comment 2 2012-11-19 14:33:17 PST
This is because an auto sized column flexbox requires 2 layouts. If you nest them, this creates 2^n layouts. Bug 102352 should fix this issue.
Carlos Garcia Campos
Comment 3 2012-11-20 09:25:34 PST
Yes, I confirm both test cases render fast with patch attached to bug #102352
Tony Chang
Comment 4 2012-12-03 11:13:21 PST
Created attachment 177291 [details] Patch
WebKit Review Bot
Comment 5 2012-12-03 11:39:29 PST
Comment on attachment 177291 [details] Patch Rejecting attachment 177291 [details] from commit-queue. Failed to run "['/mnt/git/webkit-commit-queue/Tools/Scripts/webkit-patch', '--status-host=queues.webkit.org', '-..." exit_code: 2 Last 500 characters of output: it line 152. Failed to run "['Tools/Scripts/update-webkit', '--chromium', '--force-update']" exit_code: 2 Updating OpenSource From http://git.chromium.org/external/Webkit + 1bf3e3e...e4b679b HEAD -> origin/HEAD (forced update) error: Ref refs/remotes/origin/master is at e4b679b9687bbd8bc190703dbf1027d8a33fdfb6 but expected 1bf3e3e6422a99acd8c135b162e171c31481e2dd ! 1bf3e3e...e4b679b master -> origin/master (unable to update local ref) Died at Tools/Scripts/update-webkit line 152. Full output: http://queues.webkit.org/results/15117481
WebKit Review Bot
Comment 6 2012-12-03 12:42:24 PST
Comment on attachment 177291 [details] Patch Clearing flags on attachment: 177291 Committed r136428: <http://trac.webkit.org/changeset/136428>
WebKit Review Bot
Comment 7 2012-12-03 12:42:28 PST
All reviewed patches have been landed. Closing bug.
Note You need to log in before you can comment on or make changes to this bug.