700668 - Don't enumerate all compartments for every traversal of a XPCWrappedNative

Status: RESOLVED FIXED

(Core :: XPConnect, defect)

Description

[Peter Van der Beken [:peterv]]

This is showing up in profiles in bug 696761. We should only look for expando objects if we know we ever had one for the XPCWrappedNative that we're traversing. Patch coming up.

Comment 1

[Peter Van der Beken [:peterv]]

Attachment: v1

Comment 2

[Boris Zbarsky [:bzbarsky]]

So without this patch we do O(number of live compartments) work for every XPCWrappedNative that we traverse?

That could certainly explain the profiles I'm seeing, if I have lots of compartments and lots of XPCWrappedNatives around....

Comment 3

[Peter Van der Beken [:peterv]]

https://hg.mozilla.org/integration/mozilla-inbound/rev/63e4de2dc4bb

Comment 4

[Boris Zbarsky [:bzbarsky]]

Is this something we could safely backport?

Comment 5

[Boris Zbarsky [:bzbarsky]]

For what it's worth, I just checked and I seem to have 425 compartments in the compartment map over here...  Is there any way we could just avoid the linear scan?

Comment 6

[Marco Bonardo [:mak]]

https://hg.mozilla.org/mozilla-central/rev/63e4de2dc4bb