1429970 - searchfox.org ghost window

Status: RESOLVED INCOMPLETE

(Core :: DOM: Core & HTML, defect)

Description

[Ben Kelly [:bkelly, not reviewing]]

Attachment: memory-report.json.gz

I noticed I had a searchfox ghost window today.  See attached memory report.

│    └──1.22 MB (01.01%) -- (2 tiny)
│       ├──0.79 MB (00.66%) -- top(none)/ghost/window(https://searchfox.org/mozilla-central/search?q=symbol:_ZN7mozilla3dom7workers12_GLOBAL__N_129AllowWindowInteractionHandler18FinishedWithResultENS2_21ExtendableEventResultE%2C_ZN7mozilla3dom7workers12_GLOBAL__N_123ExtendableEventCallback18FinishedWithResultENS2_21ExtendableEventResultE&redirect=false)
│       │  ├──0.58 MB (00.48%) ++ js-compartment(https://searchfox.org/mozilla-central/search?q=symbol:_ZN7mozilla3dom7workers12_GLOBAL__N_129AllowWindowInteractionHandler18FinishedWithResultENS2_21ExtendableEventResultE%2C_ZN7mozilla3dom7workers12_GLOBAL__N_123ExtendableEventCallback18FinishedWithResultENS2_21ExtendableEventResultE&redirect=false)
│       │  ├──0.13 MB (00.11%) ── layout/style-sheets
│       │  ├──0.08 MB (00.07%) ++ dom
│       │  └──0.00 MB (00.00%) ── property-tables

CC logs yield the dreaded "1 unknown edge":

bkelly@valen:/mnt/c/devel/tmp/cclogs$ /srv/heapgraph/find_roots.py cc-edges.15824.1515722827.log 00000148BB17D800
Parsing cc-edges.15824.1515722827.log. Done loading graph. 

0000014726A60000 [nsDocument normal (xhtml) https://searchfox.org/mozilla-central/search?q=symbol:_ZN7mozilla3dom7workers12_GLOBAL__N_129AllowWindowInteractionHandler18FinishedWithResultENS2_21ExtendableEventResultE%2C_ZN7mozilla3dom7workers12_GLOBAL__N_123ExtendableEventCallback18FinishedWithResultENS2_21ExtendableEventResultE&redirect=false]
    --[Preserved wrapper]--> 0000014731CF0100 [JS Object (HTMLDocument)]
    --[group_global]--> 0000014731CC7100 [JS Object (Window)]
    --[UnwrapDOMObject(obj)]--> 00000148BB17D800 [nsGlobalWindowInner # 4294967805 inner https://searchfox.org/mozilla-central/search?q=symbol:_ZN7mozilla3dom7workers12_GLOBAL__N_129AllowWindowInteractionHandler18FinishedWithResultENS2_21ExtendableEventResultE%2C_ZN7mozilla3dom7workers12_GLOBAL__N_123ExtendableEventCallback18FinishedWithResultENS2_21ExtendableEventResultE&redirect=false]

    Root 0000014726A60000 is a ref counted object with 1 unknown edge(s).
    known edges:
       00000148C23C8A10 [EditorBase] --[mDocument]--> 0000014726A60000
       00000148BE6A7430 [nsNodeInfoManager] --[mDocument]--> 0000014726A60000
       000001472A4F12C0 [FontFaceSet ] --[mDocument]--> 0000014726A60000
       00000148BB17D800 [nsGlobalWindowInner # 4294967805 inner https://searchfox.org/mozilla-central/search?q=symbol:_ZN7mozilla3dom7workers12_GLOBAL__N_129AllowWindowInteractionHandler18FinishedWithResultENS2_21ExtendableEventResultE%2C_ZN7mozilla3dom7workers12_GLOBAL__N_123ExtendableEventCallback18FinishedWithResultENS2_21ExtendableEventResultE&redirect=false] --[mDoc]--> 0000014726A60000
       0000014731CF0100 [JS Object (HTMLDocument)] --[UnwrapDOMObject(obj)]--> 0000014726A60000
       0000014726A60000 [nsDocument normal (xhtml) https://searchfox.org/mozilla-central/search?q=symbol:_ZN7mozilla3dom7workers12_GLOBAL__N_129AllowWindowInteractionHandler18FinishedWithResultENS2_21ExtendableEventResultE%2C_ZN7mozilla3dom7workers12_GLOBAL__N_123ExtendableEventCallback18FinishedWithResultENS2_21ExtendableEventResultE&redirect=false] --[mMaybeEndOutermostXBLUpdateRunner.mObj]--> 0000014726A60000

Comment 1

[Ben Kelly [:bkelly, not reviewing]]

Not sure if its related to this or a separate bug, but the report also has a detached browser.xul window.  It has an interesting heapgraph trace:

bkelly@valen:/mnt/c/devel/tmp/cclogs$ /srv/heapgraph/find_roots.py cc-edges.8460.1515722827.log 0000024006029800
Parsing cc-edges.8460.1515722827.log. Done loading graph. 

0000024005E02060 [JS Object (Window)]
    --[UnwrapDOMObject(obj)]--> 0000024006029800 [nsGlobalWindowInner # 6 inner chrome://browser/content/browser.xul]

    Root 0000024005E02060 is a marked GC object.

bkelly@valen:/mnt/c/devel/tmp/cclogs$ /srv/heapgraph/find_roots.py gc-edges.8460.1515722827.log -bro 0000024005E02060
Parsing gc-edges.8460.1515722827.log. Done loading graph.

via ScriptPreloader::CachedScript.mScript :
000002400612A5E8 [script chrome://browser/content/browser-trackingpr]
    --[sourceObject]--> 0000024005E07540 [ScriptSource <no private>]
    --[group]--> 00000240010FB1C0 [object_group]
    --[group_global]--> 0000024005E02060 [Window <no private>]

Comment 2

[Eric Rahm [:erahm]]

Have you seen this again?

Comment 3

[Ben Kelly [:bkelly, not reviewing]]

No.

Comment 4

[Eric Rahm [:erahm]]

Without STR there's not much we can do. Going to close as incomplete, but if you run into it again please feel free to reopen.