77314 - Mozilla randomly starts using ~95% CPU time when nothing is happening.

Status: RESOLVED WORKSFORME

(Core :: Networking: Cache, defect)

Description

[dylang]

I seem to get random spots where browser starts using 95% of CPU time.  This is
with build 2001042013.  I'll add more when I find a way to reliably reproduce
it.  So far I've noticed it 2 times in the past 24 hours.

Comment 1

[Andrew McMillan]

Is this happening when a dialog box is waiting on the screen?

I notice that under Linux that Moz has pegged the CPU whenever it puts up a 'do
you want this image / cookie' prompt.  That's been happening practically
forever, so there's probably already a bug filed on that problem.

Comment 2

[dylang]

No, this has only happened with the 0420 build (previous was 0316).  I noticed
it because the system seemed more slugish than usual, so I loaded top.  dnetc
and Moz were fighting it out, with Moz winning.

When I loaded my mail client 20 minutes ago, I noticed the same effect.  Again
it was Moz.  3 windows open, no dialogs, nothing loading.  Just spinning away
and away at the CPU.

Comment 3

[dylang]

Steps to reproduce with build 2001042708:

Load http://www.gibsonhax0r.net/media/winblows.html
Right click image, choose "View Image"
Watch the CPU usage peg.

I think this is related to the throbber not stoping, despite the "Image loaded
in 0.16s" being in the status area..

Comment 4

[dylang]

Another way to reprduce (including in 0.9!) is to look at an image, click back,
then view the image again (like in a dir of images you are looking at).  I think
it's some interaction between newcache and libpr0n, since you have to view the
image once before the CPU is sucked.

Comment 5

[dylang]

This behaviour seems gome in 2001052606.  Marking closed.