Improve mutation processing performance

[eoghanmurray]

Refactor record time mutation processing to improve performance

• smarter 'iteration' through the this.addedSet so that we start with nodes which already have the required nextId and parentId
• take advantage of siblings sharing the same parent, so only do parent related calculations once instead of repeatedly for every child node
• inline pushAdd (and getNextId) as we only need a single run over them

This solves pathological cases where nodes from the addedSet were pushed onto the secondary addList, possibly multiple times as pushAdd was called again each time the nextId/parentId requirements weren't met.

Previous efforts in this direction were

• perf(genadds) traverse children in reverse order #1398 "traverse children in reverse order"
• perf(rrweb): optimize random shuffled addList #1302 "optimize random shuffled addList"

Also related is #1277 "refactor recursive procedure to iterative" which we could also incorporate on top of this as it should provide orthogonal performance gains — in order to 'grasp the nettle' all at once in terms of possible breakage.

[changeset-bot]

🦋 Changeset detected

Latest commit: 7fde788

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 19 packages

Name	Type
rrweb	Patch
rrweb-snapshot	Patch
rrdom	Patch
rrdom-nodejs	Patch
rrweb-player	Patch
@rrweb/all	Patch
@rrweb/replay	Patch
@rrweb/record	Patch
@rrweb/types	Patch
@rrweb/packer	Patch
@rrweb/utils	Patch
@rrweb/web-extension	Patch
rrvideo	Patch
@rrweb/rrweb-plugin-console-record	Patch
@rrweb/rrweb-plugin-console-replay	Patch
@rrweb/rrweb-plugin-sequential-id-record	Patch
@rrweb/rrweb-plugin-sequential-id-replay	Patch
@rrweb/rrweb-plugin-canvas-webrtc-record	Patch
@rrweb/rrweb-plugin-canvas-webrtc-replay	Patch

Not sure what this means? Click here to learn what changesets are.

Click here if you're a maintainer who wants to add another changeset to this PR

[eoghanmurray]

I've cloned the plunker from #1302 from @mdellanoce
https://plnkr.co/edit/QgOXGFAFOguN2Zpa

The microtasks run after the jstree work is done, and I'm clocking 3.2s for those before this PR vs. 2.2s after.

[eoghanmurray]

Here's the benchmark output (please replicate on other machines):

                                                                                                      
title                                                   before     after   improvement   html                                             
                                                                                                      
1000x 1 DOM nodes with deeply nested children       10  2107.5    1974.1      7.0%       benchmark-dom-mutation-deep-nested.html        
1000x10 DOM nodes                                   10   384.9     370.7      3.7%       benchmark-dom-mutation.html                    
1000x10x2 DOM nodes and remove a bunch of them      10   526.6     331.9     36.0%       benchmark-dom-mutation-add-and-remove.html     
1000 DOM nodes and append into its previous looped   5   132.2      79.6     39.8%       benchmark-dom-mutation-multiple-descendant-add.h
10000 DOM nodes and move it to new container         5   586       301       48.6%       benchmark-dom-mutation-add-and-move.html       
modify attributes on 10000 DOM nodes                10    96.7      87.5      9.5%       benchmark-dom-mutation-attributes.html