24913 2009-03-28 11:52:31 -0700 [Qt] NPAPI: Excessive timer usage and high CPU load 2014-02-03 03:12:54 -0800 1 1 1 Unclassified WebKit Plug-ins 528+ (Nightly build) All All RESOLVED INVALID Performance, Qt, QtTriaged P2 Normal --- 35962 1 firuzkosimov webkit-unassigned benjamin davidtlwong hephooey_dev ismail laszlo.gombos tonikitoo oldest_to_newest 115691 0 firuzkosimov 2009-03-28 11:52:31 -0700 I use qtwebkit 4.5 on my application and qtwebkit 4.5 supports flash plugin. When I enable flash plugin and navigate to a web-page with flash (youtube.com or any other with flash banner) the cpu load jumps up to 40-70% and the process-detail column "page fault delta" goes 30,000-60,000 every second. The demo-browser that is shipped with qt 4.5 has the same problem. The steps to reproduce: 1)install qt 4.5 2)launch demo-browser from examples (notice cpu-load doesnt stay steadily when you navigate to pages without flash) 3)navigate to youtube.com 4)The cpu usage jumps to 40-70% and it doesnt go down. "page fault delta" in the process-detail column of task manager goes to 30,000-60,000 and stays at such pace. I guess the cpu load and "page fault delta" should not stay up that high during viewing web-pages with flash elements. 182686 1 davidtlwong 2010-01-20 02:28:58 -0800 I experience this problem too. Using Qt 4.6 and MSVC2008 on Windows XP. Webkit source is svn trunk r53272. It seems there are too many timer event. I modified SharedTimerQt::start() in WebCore/platform/qt/SharedTimerQt.cpp to: void SharedTimerQt::start(double fireTime) { static int zero_interval_count = 0; double interval = fireTime - currentTime(); unsigned int intervalInMS; if (interval < 0) { intervalInMS = 0; } else { interval *= 1000; intervalInMS = (unsigned int)interval; } if (intervalInMS == 0) { zero_interval_count++; if ((zero_interval_count % 10000) == 0) { printf("zero_interval_count = %d, time = %f\n", zero_interval_count, currentTime()); } } m_timer.start(intervalInMS, this); } on simple flash that only display a digital clock, It records 10,000 m_timer.start() calls, with interval equals zero, in 0.536 second on http://www.adobe.com/flashplatform/ , It records 10,000 m_timer.start() calls, with interval equals zero, in 3.165 second 204484 2 ismail 2010-03-26 03:30:30 -0700 I also see this but without any plugin, one such a page is http://en.m.wikipedia.org/wiki?search=dinasour 219418 3 benjamin 2010-04-30 03:12:42 -0700 *** Bug 35777 has been marked as a duplicate of this bug. *** 975010 4 jturcotte 2014-02-03 03:12:54 -0800 === Bulk closing of Qt bugs === If you believe that this bug report is still relevant for a non-Qt port of webkit.org, please re-open it and remove [Qt] from the summary. If you believe that this is still an important QtWebKit bug, please fill a new report at https://bugreports.qt-project.org and add a link to this issue. See http://qt-project.org/wiki/ReportingBugsInQt for additional guidelines.