Mozilla 1.6 freezes with 100% CPU utilization on



15 years ago
5 years ago


(Reporter: david.kelk, Unassigned)



Windows XP

Firefox Tracking Flags

(Not tracked)





15 years ago
User-Agent:       Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.6) Gecko/20040113
Build Identifier: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.6) Gecko/20040113

I went to with Mozilla 1.6.
Loading this page the browser froze and jumped to 100% CPU 
utilization, where it remained until I stopped it with the
task manager.
Internet Explorer 6.0.2800.1106 handles the page fine.

Reproducible: Always
Steps to Reproduce:
1.  Gp to
2.  Observe how the 1.6 browser freezes with 100% CPU

Actual Results:  
Browser froze

Expected Results:  
Browser shouldn't have froze
Yep, locks up here too. Tried with 1.6 and 1.7b on linux.

Comment 2

15 years ago
On my system (1.7b/20040420, win2k) Mozilla is NOT freezing but completely
unresponsive for 1-3 minutes.
Additionaly, it consumes about 128 MB RAM.

Maybe, this bug is related to/dup of bug 116437.

The example URL is a tar/gzipped XML-document, btw.

Comment 3

15 years ago
It took 2-3 minutes to come up on build 2004042108. When I did it a second time
to did not come up at all. This is on Windows XP Pro.
gzipped, sure.  But there's not one itty bit of tar involved.

The real issue here are all the unescaped things like "<control>", "<noBreak>",
ets scattered about the file.  These lead to a content tree that is O(N) in
depth; reflow on such a tree is very slow in Mozilla.

I did profile this, and the profile shows nothing unexpected -- a good chunk of
time taken looking for fonts, and just tons and tons of reflow happening.  Not

We already have bugs both on the fact that broken markup like this produces deep
trees and on the fact that reflow on such trees is very slow.
Keywords: perf
Whiteboard: DUPEME
Er, I was wrong.  There is in fact tar... which they claim is HTML.  The thing
inside the tarball is SO not XML, though (as soon as an XML parser hits the
</p>, it'll drop the whole thing and return a well-formedness error....

Comment 6

15 years ago
Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.8a3) Gecko/20040827

confirming the behavior: freezing for some minutes (Athlon 500: 20 min) and
allocation of memory of about 300MByte.
IE took 2-3 min to load the page.
Kenan, we know.
Product: Browser → Seamonkey
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Last Resolved: 14 years ago
Resolution: --- → EXPIRED


5 years ago
Whiteboard: DUPEME
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