443567 - Slow page loading in firefox 3.0 (high cpu usage, doesn't happen if another tab is selected)

Status: RESOLVED INCOMPLETE

(Firefox :: General, defect)

Description

[Pit Capitain]

User-Agent:       Mozilla/5.0 (Windows; U; Windows NT 5.0; de; rv:1.9) Gecko/2008052906 Firefox/3.0
Build Identifier: Mozilla/5.0 (Windows; U; Windows NT 5.0; de; rv:1.9) Gecko/2008052906 Firefox/3.0

Many (but not all) web pages are loading very slowly in firefox 3.0. The cpu usage raises to 100%. If another tab is selected while the first tab is loading, the cpu usage goes down and the first tab is loading as expected in the background. For http://www.golem.de, hitting F5 (reload) takes up to 60 seconds in the foreground, but only 5 seconds if another tab is selected after hitting F5.

Reproducible: Sometimes

Steps to Reproduce:
1. Open a tab (doesn't matter what is displayed there)
2. Open http://www.golem.de in another tab
3. Hit F5 (reload page) => loads very slowly, high cpu usage
4. Hit F5 and then select the tab opened in step 1 => normal loading and normal cpu usage
Actual Results:  
Average load times:
3. 60 seconds
4. 5 seconds

Expected Results:  
3. should have the effect of 4.

This is on Windows 2000 with all service packs and security updates installed.

Comment 1

[Doug Tidwell]

Platform:  PC, CPU=P4-2.8, 1024mb Ram, 120gb free disk space, Firefox 3.0.1

As above, when the tab is in focus it is very slow, creating an untitled tab 
and focus on it, the slow tab acts normal speed.

I always start with the untitled tab open and then create a new tab to surf with.

Awkward but effective.

Doug Tidwell
.

Comment 2

[stereo-sigi]

As above also with Windows XP SP2, Firefox 3.0.3 and 3.0.4.

My Solution is to run Firefox not with "normal" process priority but with "low" or "idle" process priority (by Windows Taskmanager or permanent with Systemexplorer).

stereo-sigi

Comment 3

[Boersenfeger]

Seems it helps, when you make with Windows XP in My Computer / DISPLAY / Preferences / Advanced / TROUBLESHOOTING / HARDWARE ACCELERATION from Full 1 Step down to 90 Percent. Two User wrote in the German Firefoxforum, that this works.
http://www.firefox-browser.de/forum/viewtopic.php?t=64328&start=30

Comment 4

[Wayne Mery (:wsmwk)]

wfm, vista, dell laptop, flash 10 Shockwave Flash 10.0 r12
Mozilla/5.0 (Windows; U; Windows NT 6.0; en-US; rv:1.9.1b2pre) Gecko/20081011 Minefield/3.1b2pre
Mozilla/5.0 (Windows; U; Windows NT 6.0; en-US; rv:1.9.0.4) Gecko/2008102920 Firefox/3.0.4

what happens with a newer version of flash, and firefox safe mode?

Comment 5

[Wayne Mery (:wsmwk)]

=> incomplete, no response to comment 4
please reopen if you can reproduce per comment 4 using FF 3.5 or newer