Closed Bug 739294 Opened 8 years ago Closed 8 years ago

Zombie compartment with ABP and


(Core :: General, defect)

Not set





(Reporter: justin.lebar+bug, Unassigned)


(Whiteboard: [MemShrink])


 * Open (NSFW, and unpleasant to boot.  I think this bug doesn't have anything to do with images, so you should be able to disable them.)

 * Command-click a few thumbnails to open them.  Each page which loads will hang the browser and show an unresponsive-script dialog.  Click "stop script".

 * Close all the tabs.

Results: Zombie compartment.

This is a particularly bad zombie because the page creates millions of objects (dom nodes?  not sure yet).  The CC falls over once these objects are detached from the page.

But more generally, I've been seeing an occasional zombie I think might be related to ABP, and perhaps this page is a good testcase.
Whiteboard: [MemShrink]
So far I reproduced the script hang and extremely slow CC but not the zombie compartment. Which Firefox version were you using?
Summary: Zombie compartment with ABP and → Zombie compartment with ABP and
14.0a1 (2012-03-26), ABP 2.0.4a3417.  I see that I'm about to get an ABP update.
The bulk of the graph is these kinds of nodes:
 4180084 nsGenericDOMDataNode
 2924563 nsGenericElement (xhtml)
 1255920 nsChildContentList

After that it falls to 22k JS objects, followed by misc. other stuff.

They have stuff that looks like:
0x1230480c0 [rc=1] nsGenericElement (xhtml) input class='newtab-control newtab-control-pin' about:newtab
0x112771920 [rc=5] nsGenericElement (xhtml) a class='newtab-link' about:newtab
FWIW, feproducing the zombie was somewhat fiddly -- it happened only about half the time.
(In reply to Justin Lebar [:jlebar] from comment #4)
> FWIW, feproducing the zombie was somewhat fiddly -- it happened only about
> half the time.

It could have to do with the particular ad that's shown on the pages.
These are mostly span nodes.

4180084 nsGenericDOMDataNode
2924056 nsGenericElement (xhtml) span 
1255920 nsChildContentList
  22968 JS Object
   1075 nsXPCWrappedJS

About 826k of these nodes are like this:
nsGenericElement (xhtml) span class='searchword'
I can't seem to reproduce with ABP 2.0.4a3420.  I do still see high heap-unclassified after closing the tab, but that's a separate issue not likely related to ABP.
The changes between ABP 2.0.4a3417 and 2.0.4a3420 are definitely unrelated - it isn't code that runs when web pages load. So the update couldn't have fixed the issue.
Sorry, I absolutely cannot reproduce it on my side. I am testing with Windows 7 because I don't have OS X but that shouldn't matter if the leak were due to ABP. The hang is easy to explain - the highlighting script is meant to highlight search keywords but due to a bug it attempts to highlight the empty string. Unfortunately that doesn't explain why something would leak here.
I guess we should forget about it.  I'm having difficulty reproducing now too.  I'd care a lot more if it were happening on a less-despicable site.

I'm sorry to have sent you on a wild goose chase, Waldimir.
Closed: 8 years ago
Resolution: --- → INCOMPLETE
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