Hangs with 100% CPU, rapid memory leak after completing large file downloading (eg. ISO, DMG)




8 years ago
8 years ago


(Reporter: wise.monkey, Unassigned)



Firefox Tracking Flags

(Not tracked)





8 years ago
User-Agent:       Mozilla/5.0 (Windows; U; Windows NT 5.2; en-US) AppleWebKit/534.10 (KHTML, like Gecko) Chrome/8.0.552.11 Safari/534.10
Build Identifier: Mozilla/5.0 (Windows; U; Windows NT 5.2; en-GB; rv: Gecko/20101012 Firefox/3.6.11

The problem generally occurs when downloading large files, such as an ISO image. The download progress reaches completion (or close to it), then the browser stops responding. The CPU utilisation for the Firefox process is at 100%. Memory footprint climbs very rapidly from roughly 250 MB to about 1600 MB, and remains at that level. Only way to control the situation is by killing the process tree for Firefox. The downloaded file is unusable and incomplete.

Reproducible: Sometimes

Steps to Reproduce:
1. Visit an ISO download link such as the Ubuntu URL given earlier.
2. Allow Firefox download manager to download the file.
3. Close download manager.
4. Wait for the download to complete in the background while surfing the web. 
Actual Results:  
Worked correctly this time.

Expected Results:  
The browser should stop responding and exhibit the symptoms described earlier.

Also worth noting that Firefox had about 20 tabs open across two application windows, over a period of several days. That is, Firefox was continually running without closing the application. Some of the tabs had flash video content (such as TED talks, etc).

Add-ons used with Firefox:

Adblock Plus
English (Australian) Dictionary
Exif Viewer
Favicon Picker
Html Validator
Hungarian Dictionary
User Agent Switcher

Foxit Reader Plugin
Google Update
Java Deployment Toolkit
Java Platform SE 6
Mozilla Default Plugin
National Instruments LabView 8.0
National Instruments LabView 8.2
RealPlayer Version Plugin
RealPlayer G2 LiveCOnnect Enabled Plugin
Shockwave Flash
Windows Presentation Foundation
Try it again without "Firebug".
Additional note: The installed Antivirus software is called after a download finished. This could be a bug in the installed AV software if this only happens after the download is complete. There is a known Firebug issue that some FB versions caused high memory usage during the download.

You can disable the AV scan if you switch browser.download.manager.scanWhenDone to false in about:config

Comment 3

8 years ago
I have no anti-virus software installed on this machine. It's difficult to replicate the problem, as there is no clear pattern to this behaviour (apart from the file size being a factor). That said, I tried without Firebug, and the download worked.

Comment 4

8 years ago
assuming you no longer see this without firebug (or newer firebug working correctly) then problem is not firefox
Last Resolved: 8 years ago
Keywords: hang
Resolution: --- → INVALID
You need to log in before you can comment on or make changes to this bug.