I'm seeing places.xul being leaked in about:memory. I have narrowed it down to a SDK addon. Analyzing the the gc/cc logs points at a Map held in a variable called "listeners" as a property of a sandbox global. Searching the sourcecode with the browser toolbox leaves sdk/event/dom as the only obvious match. Note that this is a chrome->chrome edge, so bug 695480 does not magically sever it when the window gets closed. ---- 000001F1DC959C00 [rc=4] nsGlobalWindow # 152 inner chrome://browser/content/places/places.xul 000001F1D720D000 [rc=4] nsGlobalWindow # 168 inner chrome://browser/content/places/places.xul 000001F1D5FED000 [rc=4] nsGlobalWindow # 209 inner chrome://browser/content/places/places.xul 000001F1D5330C00 [rc=4] nsGlobalWindow # 68 inner chrome://browser/content/places/places.xul 000001F1DBD1EC00 [rc=4] nsGlobalWindow # 146 inner chrome://browser/content/places/places.xul 000001F1DBF84800 [rc=4] nsGlobalWindow # 164 inner chrome://browser/content/places/places.xul 000001F1CC359000 [rc=4] nsGlobalWindow # 64 inner chrome://browser/content/places/places.xul 000001F1D6969800 [rc=4] nsGlobalWindow # 78 inner chrome://browser/content/places/places.xul $ python2 ./find_roots.py cc-edges.15748.1461940833.log 000001F1DBD1EC00 Parsing cc-edges.15748.1461940833.log. Done loading graph. 000001F1E5B17060 [JS Object (Window)] --[UnwrapDOMObject(obj)]--> 000001F1DBD1EC00 [nsGlobalWindow # 146 inner chrome://browser/content/places/places.xul] Root 000001F1E5B17060 is a marked GC object. $ python2 ./find_roots.py gc-edges.15748.1461940833.log 000001F1E5B17060 -bro Parsing gc-edges.15748.1461940833.log. Done loading graph. via mIncumbentJSGlobal : 000001F1DD2B94C0 [Sandbox 1f1dce50278] --[listeners]--> 000001F1DC217040 [Map 1f1dcfe6cd0] --[key]--> 000001F1D792A5C0 [Proxy <no private>] --[private]--> 000001F1E5B28020 [Proxy <no private>] --[private]--> 000001F1E5B17060 [Window <no private>]

note the detached window 536,146,865 B (100.0%) -- explicit ├──275,881,192 B (51.46%) -- window-objects │ ├──172,879,832 B (32.24%) -- top(none)/detached │ │ ├──166,436,720 B (31.04%) -- window(chrome://browser/content/places/places.xul) │ │ │ ├──154,253,440 B (28.77%) -- js-compartment([System Principal], about:blank) │ │ │ │ ├──116,672,528 B (21.76%) -- classes │ │ │ │ │ ├───54,162,992 B (10.10%) -- shapes │ │ │ │ │ │ ├──49,439,216 B (09.22%) -- gc-heap │ │ │ │ │ │ │ ├──37,917,464 B (07.07%) ── tree [66] │ │ │ │ │ │ │ ├───7,286,872 B (01.36%) ── dict [66] │ │ │ │ │ │ │ └───4,234,880 B (00.79%) ── base [66] │ │ │ │ │ │ └───4,723,776 B (00.88%) -- malloc-heap │ │ │ │ │ │ ├──2,312,576 B (00.43%) ── dict-tables [66] │ │ │ │ │ │ ├──1,243,040 B (00.23%) ── tree-tables [66] │ │ │ │ │ │ └──1,168,160 B (00.22%) ── tree-kids [66] │ │ │ │ │ ├───47,071,040 B (08.78%) -- class(Function)/objects │ │ │ │ │ │ ├──43,362,432 B (08.09%) ── gc-heap [66] │ │ │ │ │ │ └───3,708,608 B (00.69%) ── malloc-heap/slots [66] │ │ │ │ │ ├────9,923,136 B (01.85%) -- class(<non-notable classes>)/objects │ │ │ │ │ │ ├──5,151,936 B (00.96%) ── gc-heap [66] │ │ │ │ │ │ └──4,771,200 B (00.89%) -- malloc-heap │ │ │ │ │ │ ├──4,713,856 B (00.88%) ── slots [66] │ │ │ │ │ │ ├─────40,448 B (00.01%) ── elements/normal [66] │ │ │ │ │ │ └─────16,896 B (00.00%) ── misc [66] │ │ │ │ │ ├────2,515,712 B (00.47%) -- class(Block)/objects │ │ │ │ │ │ ├──1,292,672 B (00.24%) ── malloc-heap/slots [66] │ │ │ │ │ │ └──1,223,040 B (00.23%) ── gc-heap [66] │ │ │ │ │ ├────1,534,496 B (00.29%) -- class(Object)/objects │ │ │ │ │ │ ├────938,912 B (00.18%) ── gc-heap [66] │ │ │ │ │ │ └────595,584 B (00.11%) ── malloc-heap/slots [66] │ │ │ │ │ ├────1,432,256 B (00.27%) ── class(With)/objects/gc-heap [66] │ │ │ │ │ ├───────16,512 B (00.00%) ── class(WithTemplate)/objects/gc-heap │ │ │ │ │ └───────16,384 B (00.00%) ── class(Proxy)/objects/gc-heap │ │ │ │ ├───17,580,288 B (03.28%) ── compartment-tables [66] │ │ │ │ ├───16,117,712 B (03.01%) -- scripts │ │ │ │ │ ├──12,866,048 B (02.40%) ── gc-heap [66] │ │ │ │ │ └───3,251,664 B (00.61%) ── malloc-heap/data [66] │ │ │ │ ├────2,703,360 B (00.50%) ── cross-compartment-wrapper-table [66] │ │ │ │ ├──────749,760 B (00.14%) ── type-inference/object-type-tables [66] │ │ │ │ └──────429,792 B (00.08%) ── sundries/malloc-heap [66] │ │ │ ├───11,847,392 B (02.21%) -- dom │ │ │ │ ├───8,510,432 B (01.59%) ── element-nodes [66] │ │ │ │ ├───3,323,232 B (00.62%) ── other [66] │ │ │ │ └──────13,728 B (00.00%) ── text-nodes [66] │ │ │ ├──────222,224 B (00.04%) ── style-sheets [66] │ │ │ └──────113,664 B (00.02%) ── property-tables [66]

The sandbox's vars from the gc log. This is matches up quite nicely with https://github.com/mozilla/addon-sdk/blob/f5fab7b242121dccfa4e55ac80489899bb9f2a41/lib/sdk/event/dom.js 000001F1DD2B94C0 B Sandbox 1f1dce50278 > 000001F1DD58A850 B group > 000001F1DD5BF6C8 B shape > 000001F1DD581E00 B CLASS_OBJECT(Date) > 000001F1DD581B80 B CLASS_OBJECT(Math) > 000001F1DD5A0DC0 B CLASS_OBJECT(Number) > 000001F1DD5A0840 B CLASS_OBJECT(Int16Array) > 000001F1DD5A0A80 B CLASS_OBJECT(Intl) > 000001F1DD59D200 B **UNKNOWN SLOT 55** > 000001F1DD581B00 B **UNKNOWN SLOT 56** > 000001F1DD2BA640 B **UNKNOWN SLOT 57** > 000001F1DD5637F0 B **UNKNOWN SLOT 74** > 000001F1DD6A52E0 B **UNKNOWN SLOT 88** > 000001F1DD581E00 B Object > 000001F1DD581B80 B Function > 000001F1DD5A0DC0 B Array > 000001F1DD5A0A80 B Map > 000001F1DD5A0500 B **UNKNOWN SLOT 152** > 000001F1DD581B40 B **UNKNOWN SLOT 154** > 000001F1DD5637C0 B **UNKNOWN SLOT 164** > 000001F1DB733D60 B **UNKNOWN SLOT 165** > 000001F1CC06E920 B **UNKNOWN SLOT 166** > 000001F1E3950E20 B **UNKNOWN SLOT 183** > 000001F1DD59D220 B **UNKNOWN SLOT 184** > 000001F1DD6A53A0 B **UNKNOWN SLOT 189** > 000001F1DD5A0500 B eval > 000001F1DD5A0540 B XPCNativeWrapper > 000001F1DD5A05C0 B dump > 000001F1DD59D6C0 B emit > 000001F1DD59D8C0 B unload > 000001F1DD6A5320 B Promise > 000001F1DC217040 B listeners > 000001F1D9392C40 B getWindowFrom > 000001F1DD5A0940 B removeFromListeners > 000001F1DD5A0980 B open > 000001F1DD59DAA0 B ShimWaiver > 000001F1DD59D260 B protoAndIfaceCache[i] > 000001F1DD6A5320 B protoAndIfaceCache[i]

Irakli, do you know who can take a look at this?

Since this is the last remaining GC edge making it weak should do the job.

You need to ask a specific person for review. Looking at the hg blame for the file you are modifying might give you some hints about who to ask.

I'm also about to post some patches in bug 1267693 that might help here.

Fixed the patch to be based off m-c and added a commit message. https://treeherder.mozilla.org/#/jobs?repo=try&revision=13f14feac424

New patch. Bug 1221292 moved the weak map key enumeration to ThreadSafeChromeUtils but MDN didn't mention that.

Pushed by cbook@mozilla.com: https://hg.mozilla.org/integration/fx-team/rev/f4a3b8f1d56d Fix leak in sdk/event/dom. r=gabor

If you'd like to uplift this to Aurora, go to "details" for the patch, set approval‑mozilla‑aurora to ?, and fill out the form. Thanks for fixing this!

Comment on attachment 8769499 [details] [diff] [review] Bug-1268898-Fix-window-leak.patch Approval Request Comment [Feature/regressing bug #]: Addon-sdk which is used both internally to firefox and in addons. [User impact if declined]: Memory leaks degrading performance over time. [Describe test coverage new/current, TreeHerder]: existing functionality is tested in addon-sdk/test/test-event-dom.js [Risks and why]: Should be minimal. Public APIs are not affected and the altered code only runs on addon unload. [String/UUID change made/needed]: No This should go along with the uplift in bug 1267693. Based on some gc/cc logs I've looked at some leaks require both fixes.

Comment on attachment 8769499 [details] [diff] [review] Bug-1268898-Fix-window-leak.patch Fix leak, taking it.

remote: https://hg.mozilla.org/releases/mozilla-aurora/rev/02b002977b46