856750 - Frequent main-thread hangs in nsStreamListenerTee::OnStopRequest

Status: NEW

(Core :: Networking, defect, P3)

Description

[Vladan Djeric (:vladan)]

I frequently notice main thread hangs lasting a second or two while browsing. When I check my about:telemetry page, I almost always see reports of hangs with the following stacks:

NtWaitForSingleObject (in wntdll.pdb)
RtlpDeCommitFreeBlock (in wntdll.pdb)
PR_Lock (in nss3.pdb)
nsCOMPtr_base::assign_with_AddRef(nsISupports *) (in xul.pdb)
nsStreamListenerTee::OnStopRequest(nsIRequest *,nsISupports *,tag_nsresult) (in xul.pdb)
mozilla::net::nsHttpChannel::OnStopRequest(nsIRequest *,nsISupports *,tag_nsresult) (in xul.pdb)
nsInputStreamPump::OnStateStop() (in xul.pdb)
nsInputStreamPump::OnInputStreamReady(nsIAsyncInputStream *) (in xul.pdb)
nsInputStreamReadyEvent::Run() (in xul.pdb)

Comment 1

[Vladan Djeric (:vladan)]

I captured a profile:

http://people.mozilla.com/~bgirard/cleopatra/#report=9a437e766f61a080e37a6e2a74239a306a685f6b

I'm guessing this might be lock contention with the network cache?

Comment 2

[Firefox Bug Husbandry Bot]

Bulk change to priority: https://bugzilla.mozilla.org/show_bug.cgi?id=1399258

Comment 3

[Firefox Bug Husbandry Bot]

Bulk change to priority: https://bugzilla.mozilla.org/show_bug.cgi?id=1399258