Closed Bug 621607 Opened 11 years ago Closed 4 years ago

A better way to find misbehaving add-ons (memory leaking extensions specifically)


(Toolkit :: Add-ons Manager, enhancement)

Not set





(Reporter: piyush_soni, Unassigned)


User-Agent:       Mozilla/5.0 (Windows; U; Windows NT 6.1; en-US; rv: Gecko/20101203 Firefox/3.6.13
Build Identifier: Mozilla/5.0 (Windows; U; Windows NT 6.1; en-US; rv: Gecko/20101203 Firefox/3.6.13

Everybody knows Firefox is a memory hog. I also know of the ages old phrase "It's not Firefox. It's your add-ons", and the standard memory diagnostic techniques (safe mode/disabling add-ons, enabling them one-by-one/creating new Profile etc.). But if you have too many Extensions and Plugins - it's just too difficult to find one (or more). Firefox should provide a better way of finding which add-on(/Plugin/webpage) has caused how much memory usage or which one has caused a 'high rate of memory usage increase'. I have no idea if it is possible or feasible. Basically Firefox should make it easier for users to know and report memory leaking add ons. 


Reproducible: Always

Steps to Reproduce:
1. Install some of the most popular Firefox add-ons (including FireBug), some not so popular ones, and standard video playing codecs/plugins + QuickTime, Silverlight, Flash plugins. 
2. Do standard activity - play with FireBug, watch a few videos for an hour or two.
3. See Firefox ruthlessly goes above 1.2 GB of RAM usage, and high CPU usage too. 
4. Restart Firefox with all the pages save on quit, see that this time not so bad. 
Actual Results:  
No easy way of knowing who was causing all this memory leaks. 

Expected Results:  
Some quick way of finding as soon as an add-on causes high memory/CPU usage.
Component: General → Add-ons Manager
Product: Firefox → Toolkit
QA Contact: general → add-ons.manager
Whiteboard: dupeme
Closed: 11 years ago
Resolution: --- → DUPLICATE
Duplicate of bug: 534020
Bug 534020 is about plugins and not extensions. We should keep that separated.
Ever confirmed: true
Resolution: DUPLICATE → ---
Jennifer has been uploaded a mockup to bug 534020 a while back. You can see this as attachment 427380 [details].
Whiteboard: dupeme
about:memory is the best tool we have for finding memory leaks in add-ons.  See and for documentation, and bug 700547 for a list of known leaky add-ons.

Is that enough for this bug to be marked fixed?  Ideally we'd have per-extension memory reporting, but I don't know how to do that.
Don't know about the other ones, but I think about:memory is enough for marking it fixed. It doesn't give much useful information and not at all in a way a layman can understand. Mostly, when I click those 'Reduce Memory Usage', nothing happens. The memory firefox is currently taking remains almost the same (sometimes increases!)

So if it is currently not feasible to have a good implementation for this, I'd suggest let's keep it open.
Aah. Typo. about:memory is *not* enough for marking it fixed.
Per policy at If this bug is not an enhancement request or a bug not present in a supported release of Firefox, then it may be reopened.
Closed: 11 years ago4 years ago
Resolution: --- → INACTIVE
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