Bug 53990

Summary: fast/forms/search-event-delay.html is flakey
Product: WebKit Reporter: Csaba Osztrogonác <ossy>
Component: Tools / TestsAssignee: Nobody <webkit-unassigned>
Status: RESOLVED CONFIGURATION CHANGED    
Severity: Major CC: ahmad.saleem792, darin, mjs
Priority: P2    
Version: 528+ (Nightly build)   
Hardware: All   
OS: All   

Description Csaba Osztrogonác 2011-02-08 03:04:27 PST
fast/forms/search-event-delay.html fails sometimes.
For example the latest fail on the Qt bot:
http://build.webkit.org/results/Qt%20Linux%20Release/r77916%20%2827877%29/fast/forms/search-event-delay-pretty-diff.html

--- /home/webkitbuildbot/slaves/release32bit/buildslave/qt-linux-release/build/layout-test-results/fast/forms/search-event-delay-expected.txt	2011-02-08 01:30:54.550056855 -0800
+++ /home/webkitbuildbot/slaves/release32bit/buildslave/qt-linux-release/build/layout-test-results/fast/forms/search-event-delay-actual.txt	2011-02-08 01:30:54.550056855 -0800
@@ -6,4 +6,4 @@
 
 The two rows below should match.
 0.5 0.4 0.3 0.2 0.2 0
-0.5 0.4 0.3 0.2 0.2 0
+0.5 0.4 0.3 0.2 0.4 0
Comment 1 Csaba Osztrogonác 2011-02-08 03:10:47 PST
This test introduced in http://trac.webkit.org/changeset/19336 .
I cc-ed Darin as author and Maciej as reviewer of this changeset.

Have you got any idea what cause this rare flakey fail and how can we fix it?
Comment 2 Darin Adler 2011-02-08 07:46:37 PST
My guess is the flakiness is caused by the fact that it’s a test that involves real time.
Comment 3 Darin Adler 2011-02-09 07:45:55 PST
If the bot is heavily loaded, then the test will fail. That number means that it took 0.2 seconds.

To make this test more reliable we could come up with a way to measure time that is independent of wall time and make WebCore's logic use that time system, at least when running tests.
Comment 4 Alexey Proskuryakov 2013-10-01 13:48:36 PDT
Marked as flaky in <http://trac.webkit.org/r156732>. The test frequently fails on debug bots. It also failed on my local run of release build (with --child-processes=1, so CPU was not heavily loaded).

My local result:

 The two rows below should match.
 0.5 0.4 0.3 0.2 0.2 0
-0.5 0.4 0.3 0.2 0.2 0
+0.6 0.5 0.4 0.3 0.3 0.1