Created attachment 8412601 [details]
memory diff before/after enabling
Recently, I noticed that my fairly modest Firefox session (4 pinned tabs) was using over 600MB on startup, which is much higher than it used to. After debugging for awhile, I was able to track it down to Adblock Plus being the main source.
On a session with only Treestatus, Add-ons Manager, and about:memory loaded, the memory usage jumped by 150MB within seconds of enabling Adblock Plus. This doesn't appear to be the same as bug 988266 as style-sets only account for ~5MB of the increase. It mostly looks like a big pile of JS stuff.
Adblock Plus is configured with up-to-date EasyList and EasyPrivacy lists enabled and nothing else.
Attached is a diff of about:memory before and after enabling Adblock Plus. I made sure to minimize memory usage before saving both reports.
Built from http://hg.mozilla.org/mozilla-central/rev/98e0a9b57414
--enable-application=browser --enable-official-branding --enable-optimize=-O2 --target=x86_64-pc-mingw32 --host=x86_64-pc-mingw32 --enable-debug-symbols --disable-debug --disable-mochitest --disable-tests --disable-accessibility --disable-crashreporter --disable-parental-controls --disable-safe-browsing --disable-updater
Created attachment 8412613 [details]
memory diff before/after enabling with recent Aurora build
Same procedure and profile as above, but with a recent Aurora build off TBPL.
Created attachment 8412617 [details]
diff of trunk vs. aurora after startup
Same baseline data as the two diffs above, just comparing the startup memory usage of trunk vs. aurora since I've got it.
Created attachment 8412618 [details]
diff of trunk vs. aurora after abp enabled
And after ABP enabled
I can reproduce. The base difference at start-up appears to be about 60--80 MiB (on Linux64), and that gradually increases with the number of iframes (although style-sets increases much more quickly, as mentioned in bug 988266).
I just wrote a blog post about ABP's effect on Firefox's memory usage (https://blog.mozilla.org/nnethercote/2014/05/14/adblock-pluss-effect-on-firefoxs-memory-usage/), in order to raise awareness of this issue.
(In reply to Nicholas Nethercote [:njn] from comment #4)
> I can reproduce. The base difference at start-up appears to be about 60--80
> MiB (on Linux64), and that gradually increases with the number of iframes
> (although style-sets increases much more quickly, as mentioned in bug
The style-sets problem (bug 988266) has now been fixed thanks to heycam's work in bug 77999.
> The style-sets problem (bug 988266) has now been fixed thanks to heycam's
> work in bug 77999.
As a result of this, I've retitled this bug so it's just about the fixed overhead, which I measured (in comment 4) to be about 60--80 MiB on Linux64.