"new identity" leaks memory in eventSuppressor.suppressEventHandling()

According to skruffy, each tab that's open when you click 'new identity' contributes to more lost memory.

For normal tabs, when you close them, eventually the memory from them garbage collects or otherwise returns to the system. For tabs closed by new identity, it remains lost.

added component::applications/tor browser ff78-esr gitlab-tb-torbutton interview owner::tbb-team parent::18047 priority::medium severity::major status::new tbb-newnym tbb-performance-leaking tbb-torbutton type::defect labels

This is apparently new in FF 17.0.8 and was not present in 17.0.7.

Or maybe that last comment is wrong.

Trac:
Cc: N/A to g.koppen@jondos.de

According to skruffy, this is due to the call to eventSuppressor.suppressEventHandling() during torbutton_disable_all_js(). Removing it eliminates the leak. Possibly DOM events are required to unref all of the objects in a window?

Oddly, the leaks still happen if JS is fully disabled, at least via NoScript's disabling.

Trac:
Summary: "new identity" leaks memory? to "new identity" leaks memory in

Trac:
Summary: "new identity" leaks memory in to "new identity" leaks memory in evenSuppressor.suppressEventHandling()

The leaked memory is primarily concentrated in the 'heap-unclassified' section of about:memory, and this is reproducible even if you just mash New Identity a bunch of times without loading any web pages.

Probably time to dig a bit deeper and try out some of these: https://wiki.mozilla.org/Performance:Leak_Tools.

Actually, there's quite a few window objects from previous new identity sessions in about:memory too.

Still an issue with FF24?

Trac:
Keywords: N/A deleted, tbb-newnym added

Trac:
Keywords: N/A deleted, interview added

Trac:
Owner: mikeperry to tbb-team
Component: TorBrowserButton to Tor Browser
Keywords: N/A deleted, tbb-torbutton added

Still an issue with FF24? Yes, it is still an issue with Firefox. All open pages adds content to never purgeable garbage of Firefox's memory if to choose "new identity". Some of used urls visible as window-objects via about:memory (with verbose report enabled)

Btw, bug which was reason to use of eventSuppressor.suppressEventHandling() now marked as fixed.

It's time to remove eventSuppressor.suppressEventHandling() from Torbutton shipped with Tor Browser 4.x and to claim this bug fixed.

https://bugzilla.mozilla.org/show_bug.cgi?id=409737 was fixed, Torbutton still using workaround https://gitweb.torproject.org/torbutton.git/tree/src/chrome/content/torbutton.js#n2675 If to remove this code then this ticket could be marked as fixed.

Trac:
Status: new to needs_information

Trac:
Owner: tbb-team to mikeperry
Status: needs_information to assigned

Trac:
Status: assigned to needs_information

Trac:
Component: Tor Browser to Torbutton

Trac:
Component: Torbutton to Tor Browser

Trac:
Summary: "new identity" leaks memory in evenSuppressor.suppressEventHandling() to "new identity" leaks memory in eventSuppressor.suppressEventHandling()