1034566 - Extend GC tracing with information about finalizers and types

Status: RESOLVED FIXED

(Core :: JavaScript: GC, defect)

Description

[Jon Coppeard (:jonco)]

We can get some useful information by looking at object lifetimes broken down by whether they have a finalizer, and by their type.

Comment 1

[Jon Coppeard (:jonco)]

Attachment: 1 - Some refactoring of gcstats.cpp

Comment 2

[Jon Coppeard (:jonco)]

Attachment: 2 - Trace whether objects have finalizers

Comment 3

[Jon Coppeard (:jonco)]

Attachment: 3 - Trace object types

Comment 4

[Jon Coppeard (:jonco)]

Latest results are up here: http://people.mozilla.org/~jcoppeard/gcstats/

Comment 5

[Terrence Cole [:terrence]]

Comment on attachment 8450916 [details] [diff] [review]
3 - Trace object types

Review of attachment 8450916 [details] [diff] [review]:
-----------------------------------------------------------------

::: js/src/devtools/gctrace/gcstats.cpp
@@ +451,5 @@
> +        if (objectCountByType.at(i) > minObjectCount)
> +            topTypes.push_back(i);
> +    }
> +    std::sort(topTypes.begin(), topTypes.end(),
> +              [] (TypeId a, TypeId b) { return objectCountByType.at(a) > objectCountByType.at(b); });

Yay, lambdas!

Comment 6

[Jon Coppeard (:jonco)]

https://hg.mozilla.org/integration/mozilla-inbound/rev/ced38bdb659b
https://hg.mozilla.org/integration/mozilla-inbound/rev/e57e4378a1c1
https://hg.mozilla.org/integration/mozilla-inbound/rev/047082ad1464

Comment 7

[Wes Kocher (:KWierso) (Not reading bugmail; email directly if needed)]

https://hg.mozilla.org/mozilla-central/rev/ced38bdb659b
https://hg.mozilla.org/mozilla-central/rev/e57e4378a1c1
https://hg.mozilla.org/mozilla-central/rev/047082ad1464