1597750 - Consider to use medium high priority queue for speculative load runnable

Status: RESOLVED DUPLICATE of bug 1800381

(Core :: DOM: HTML Parser, defect, P2)

Description

[Olli Pettay [:smaug][[e-mail]]]

We should probably try to flush speculative loads asap.

Comment 1

[Olli Pettay [:smaug][[e-mail]]]

Attachment: Bug 1597750 - Consider to use medium high priority queue for speculative load runnable, r=hsivonen

Comment 2

[Olli Pettay [:smaug][[e-mail]]]

https://treeherder.mozilla.org/#/jobs?repo=try&revision=5a8dd7017c9563be6ba11b6e4dce47c88fc38971

Comment 3

[Olli Pettay [:smaug][[e-mail]]]

reference perf numbers https://treeherder.mozilla.org/#/jobs?repo=try&revision=32d183b5a062b5842628f8160c6282342e8cabc7

Comment 4

[Olli Pettay [:smaug][[e-mail]]]

https://treeherder.mozilla.org/#/jobs?repo=try&revision=6767211b57548e6c4ce3783e5e15060aac126c1c

Comment 5

[Andrew Creskey [:acreskey]]

I'm wondering what would be the best way to evaluate this.
In our CI tests we connect via https proxy which disables speculative connection in some codepaths.
And there's no latency in that environment, so we may not see the impact.
Maybe a local browsertime run with network throttling could at least give us a clue as whether or not this is worth pursuing.

Comment 6

[Andrew Creskey [:acreskey]]

Oh, I think the work here was already done in bug 1800381 as we now send this with RenderBlocking priority:
https://searchfox.org/mozilla-central/rev/00e348d6935d99a089c318f4512b22327c22154b/parser/html/nsHtml5StreamParser.cpp#1817-1819

Comment 7

[Andrew Creskey [:acreskey]]

Before I realized that we had already increased the priority of the runnable, I added a temporary PerfStat to see if we could measure an improvement in the delay it takes the Htm5SpeculativeLoad runnable to executre.

And in fact if I rollback the change from Bug 1800381 as the baseline and compare against the current, we see a whole bunch high-confidence improvements in that PerfStat:

https://treeherder.mozilla.org/perfherder/compare?originalProject=try&originalRevision=9ef513dab6fcdd15b1395438b21157e63f42a335&newProject=try&newRevision=1a3e2b5a765b742ec2bfd41396fabe665cfcdf7e&page=1&framework=13&filter=html5

Smaug: I think we can close this as dupe of bug 1800381 unless you can think of anything else to do here?

Comment 8

[Olli Pettay [:smaug][[e-mail]]]

Ah, this does look like a dup. There might be still some more tweaks to do, but we can file followups.