Bug 142041

Summary: [EFL][GTK] REGRESSION(180602): It made fast/workers test timeout
Product: WebKit Reporter: Csaba Osztrogonác <ossy>
Component: JavaScriptCoreAssignee: Nobody <webkit-unassigned>
Status: RESOLVED FIXED    
Severity: Critical CC: cgarcia, chavarria1991, clopez, gyuyoung.kim, mark.lam, msaboff, ossy
Priority: P1    
Version: 528+ (Nightly build)   
Hardware: Unspecified   
OS: Unspecified   
Bug Depends on:    
Bug Blocks: 141990    

Description Csaba Osztrogonác 2015-02-26 02:41:59 PST
GTK:
- before: https://build.webkit.org/builders/GTK%20Linux%2064-bit%20Release%20%28Tests%29/builds/6464
- after: https://build.webkit.org/builders/GTK%20Linux%2064-bit%20Release%20%28Tests%29/builds/6465

EFL:
- before: https://build.webkit.org/builders/EFL%20Linux%2064-bit%20Release%20WK2/builds/20006
- after: https://build.webkit.org/builders/EFL%20Linux%2064-bit%20Release%20WK2/builds/20021

Unfortunately there were build break between r180585-r180603 due to the "awesome" 
WK2 owner model. But I checked it manually, and fast/workers tests pass on r180601 
with the buildfix applied, so r180602 must be the culprit.
Comment 1 Csaba Osztrogonác 2015-02-26 03:47:59 PST
I skipped fast/workers tests on EFL bots, because it increased the testing
time from 15 minutes to 35 minutes, and then the bot died with timeout.

Skip landed in http://trac.webkit.org/changeset/180671 .
Comment 2 Mark Lam 2015-02-26 09:20:53 PST
One of the side effects of r180602 is that it results in more threads being scanned by GC.  Specifically, that means a VM on the main thread will also scan the stacks of all worker threads because they have had a VM run on them before.  This means they are doing more work, though we had anticipated that it shouldn’t be that costly.

I’ll prepare a test patch to see if eliminating / reducing this unnecessary work makes a difference.
Comment 3 Mark Lam 2015-02-26 15:37:15 PST
FYI, the r180602 patch was rolled out in r180690: <http://trac.webkit.org/r180690>.
Comment 4 Mark Lam 2015-02-26 21:08:33 PST
With the solution for https://bugs.webkit.org/show_bug.cgi?id=141990, the GTK test bot seems to be happy.  The previously skipped tests have been un-skipped when I rolled out r180690 earlier.

Nothing more to do.  Closing this bug.