Bug 86732 – Web Inspector: speed-up markQueriableHeapObjects function.

• Status: RESOLVED
• Resolution: FIXED
• Component: Web Inspector (Deprecated)

[Ilya Tikhonovsky]

inline getters

RESULT heap-snapshot: _markQueriableHeapObjects= 879 ms
vs
RESULT heap-snapshot: _markQueriableHeapObjects= 42 ms

[Ilya Tikhonovsky]

Created attachment 142474 [details]
Patch

[Yury Semikhatsky]

Comment on attachment 142474 [details]
Patch

View in context: https://bugs.webkit.org/attachment.cgi?id=142474&action=review

> Source/WebCore/inspector/front-end/HeapSnapshot.js:-1180
> -                list.push(iter.edge.node.nodeIndex);

Please revert this part.

> Source/WebCore/inspector/front-end/HeapSnapshot.js:1197
> +                         ? nodes[nodeIndex + firstEdgeIndexOffset + nodeFieldCount]

Please realign these two lines.

> Source/WebCore/inspector/front-end/HeapSnapshot.js:1213
> +        this._flags = new Uint32Array(this.nodeCount);

Does it make any difference?

[Ilya Tikhonovsky]

Committed r117545: <http://trac.webkit.org/changeset/117545>

[Ilya Tikhonovsky]

(In reply to comment #2)
> (From update of attachment 142474 [details])
> View in context: https://bugs.webkit.org/attachment.cgi?id=142474&action=review
> 
> > Source/WebCore/inspector/front-end/HeapSnapshot.js:-1180
> > -                list.push(iter.edge.node.nodeIndex);
> 
> Please revert this part.

done

> 
> > Source/WebCore/inspector/front-end/HeapSnapshot.js:1197
> > +                         ? nodes[nodeIndex + firstEdgeIndexOffset + nodeFieldCount]
> 
> Please realign these two lines.

done

> 
> > Source/WebCore/inspector/front-end/HeapSnapshot.js:1213
> > +        this._flags = new Uint32Array(this.nodeCount);
> 
> Does it make any difference?

This line is the root for the sake of which all the patch has been made.
Before the patch the array was sparse. Actually it was a hash map.
Now we have no memory overhead and we can make it external.
It gives us an additional speed boost and reduces js heap footprint.