Bug 82325 – Web Inspector: Speed up heap profiler snapshot parsing

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

[Alexei Filippov]

It can be made faster.

[Alexei Filippov]

Created attachment 134031 [details]
Patch

[Ilya Tikhonovsky]

Comment on attachment 134031 [details]
Patch

View in context: https://bugs.webkit.org/attachment.cgi?id=134031&action=review

> Source/WebCore/inspector/front-end/HeapSnapshot.js:1231
> +        for (var i = 1, l = nodes.length; i < l; ++count) {

rootNodeIndex?

> Source/WebCore/inspector/front-end/HeapSnapshot.js:1238
> +        for (var i = 1, l = nodes.length; i < l; ++count) {

ditto

> Source/WebCore/inspector/front-end/HeapSnapshot.js:1282
> +        var indexArray = this._dominatedIndex = new Int32Array(nodeCount + 1);

Uint32Array

> Source/WebCore/inspector/front-end/HeapSnapshot.js:1291
> +        var dominatedNodes = this._dominatedNodes = new Int32Array(nodeCount + 1);

ditto

[Yury Semikhatsky]

Comment on attachment 134031 [details]
Patch

View in context: https://bugs.webkit.org/attachment.cgi?id=134031&action=review

> Source/WebCore/inspector/front-end/HeapSnapshot.js:1227
> +        var edgesCountOffset = this._edgesCountOffset;

We can just inline these as there is no performance gain.

> Source/WebCore/inspector/front-end/HeapSnapshot.js:1272
> +        var nodeIndexes = this.nodeIndexes;

Consider inlining these as well.

> Source/WebCore/inspector/front-end/HeapSnapshot.js:1282
> +        var indexArray = this._dominatedIndex = new Int32Array(nodeCount + 1);

Int32Array -> Uint32Array

> Source/WebCore/inspector/front-end/HeapSnapshot.js:1291
> +        var dominatedNodes = this._dominatedNodes = new Int32Array(nodeCount + 1);

Int32Array -> Uint32Array, length of the dominatedNodes array should be equal to sum of all indexArrat values at this point, not nodeCount+1

> Source/WebCore/inspector/front-end/HeapSnapshot.js:1389
> +        var flags = this._flags;

Please inline these.

> Source/WebCore/inspector/front-end/HeapSnapshot.js:1403
> +            edge._edges = node.rawEdges;

Why not take node.edges? Could you at least introduce a public setter on the edge?

[Alexei Filippov]

Comment on attachment 134031 [details]
Patch

View in context: https://bugs.webkit.org/attachment.cgi?id=134031&action=review

>> Source/WebCore/inspector/front-end/HeapSnapshot.js:1227
>> +        var edgesCountOffset = this._edgesCountOffset;
> 
> We can just inline these as there is no performance gain.

done

>> Source/WebCore/inspector/front-end/HeapSnapshot.js:1231
>> +        for (var i = 1, l = nodes.length; i < l; ++count) {
> 
> rootNodeIndex?

done

>> Source/WebCore/inspector/front-end/HeapSnapshot.js:1238
>> +        for (var i = 1, l = nodes.length; i < l; ++count) {
> 
> ditto

done

>> Source/WebCore/inspector/front-end/HeapSnapshot.js:1272
>> +        var nodeIndexes = this.nodeIndexes;
> 
> Consider inlining these as well.

done

>>> Source/WebCore/inspector/front-end/HeapSnapshot.js:1291
>>> +        var dominatedNodes = this._dominatedNodes = new Int32Array(nodeCount + 1);
>> 
>> ditto
> 
> Int32Array -> Uint32Array, length of the dominatedNodes array should be equal to sum of all indexArrat values at this point, not nodeCount+1

it is nodeCount - 1, as each node except for root has one dominator.

>> Source/WebCore/inspector/front-end/HeapSnapshot.js:1389
>> +        var flags = this._flags;
> 
> Please inline these.

done

>> Source/WebCore/inspector/front-end/HeapSnapshot.js:1403
>> +            edge._edges = node.rawEdges;
> 
> Why not take node.edges? Could you at least introduce a public setter on the edge?

node.edges is an iterator which I'd like to avoid. Don't wanna introduce a setter, we don't have them for nodeIndex and edgeIndex.

[Alexei Filippov]

Created attachment 134056 [details]
Patch

[Yury Semikhatsky]

Comment on attachment 134056 [details]
Patch

Clearing flags on attachment: 134056

Committed r112271: <http://trac.webkit.org/changeset/112271>

[Yury Semikhatsky]

All reviewed patches have been landed.  Closing bug.