433170 - FF 3 beta 5 experiences long pauses when scrolling, page fault rate inscreases

Status: RESOLVED INCOMPLETE

(Firefox :: General, defect)

Description

[Lee Dilkie]

User-Agent:       Mozilla/5.0 (Windows; U; Windows NT 5.1; en-GB; rv:1.9b5) Gecko/2008032620 Firefox/3.0b5
Build Identifier: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-GB; rv:1.9b5) Gecko/2008032620 Firefox/3.0b5

If I have a number of tabs open (dozen or so) and I leave FF running for a day or so I see a climb in memory (VM size as reported by windows task manager) to something on the order of 300M. Then I also see these "pregnant" pauses when trying to scroll a window. All input, scrolling, clicking on scrollbar, clicking a link or button, is ignored for a couple of seconds. When the pause stops, the input is handled. At the same time, I notice that the firefox application page fault delta increases from 0 to many thousands of faults per second. This happens periodically (maybe every 30 seconds). During this time all FF activities halt. For example, playing a video on youtube will halt for a few seconds every time.

I suspect some sort of garbage collection is taking place. I can't say for sure, but as a programmer mself, it sure has that "feel" to it.

Reproducible: Always

Steps to Reproduce:
1. have a couple of dozen tabs open
2. Wait a day or so.
3. surf the net... notice things like scrolling windows have periods wher they pause.
4. Use windows task manager and watch firefox. Add the "PF Delta" column. Notice that periodicly the PF delta rate goes from 0 to some big value. The time of these occurances coorsponds to the pauses in FF.

Actual Results:  
pauses in FF

Expected Results:  
I expect no pauses and FF to respond to input. Especially on an essentially idle condition (scrolling an open page is essentially idle).

This behaviour didn't happen in FF 2.0 and I *think* it did happen in FF 3 beta 4.

I can temporarly fix the problem by exiting firefox (and waiting until it really exits which can take 10 seconds or so) and then restarting. Even with all the same tabs open, the problem won't occur for a day or so.

BTW. When I do restart FF, the memory usage for the same tabs when down from 300M to 80M.

Comment 1

[Leon Out]

I am experiencing what I believe is the same problem on Mac OS X 10.5.4. After running FF for a day or two, frequent pauses become a very annoying problem. I think this is a cross-platform problem. Can we change the Platform to All?

Comment 2

[Hiroto Kagotani]

I encountered the same problem with Firefox 3.0.0--3.0.3 on Windows XP.
Taskmanager said Firefox was getting more and more memory during the pause.
 
After creating a new profile, migrating bookmarks, cookies and passwords from
the old one and installing all my favorite add-ons, Firefox seems much quicker
and not annoying me so far.

Only using safe-mode was not sufficient. New profile was required. What in the
old profile caused the problem is not identified.

Comment 3

[Tyler Downer [He/Him]]

Reporter, are you still seeing this issue with Firefox 3.6.x or later in safe mode? If not, please close. These links can help you in your testing.
http://support.mozilla.com/kb/Safe+Mode
http://support.mozilla.com/kb/Managing+profiles

Comment 4

[Tyler Downer [He/Him]]

No reply, INCOMPLETE. Please retest with Firefox 3.6.10 or later and a new profile (http://support.mozilla.com/kb/Managing+profiles). If you continue to see this issue with the newest firefox and a new profile, then please comment on this bug.