1489633 - consider to run GC/CC slices less often when page is loading

Status: NEW

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

Description

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

Kind of bringing back some behavior of bug 366393, though that was before any incremental collectors or idle scheduling or CC optimizations or anything.

Comment 1

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

Attachment: less_likely_collectors_during_pageload.diff

remote: 
remote: Follow the progress of your build on Treeherder:
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remote: It looks like this try push has talos jobs. Compare performance against a baseline revision:
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remote: recorded changegroup in replication log in 0.014s

Comment 2

[Jon Coppeard (:jonco)]

I'm not against this, but note that running slices less often can result in the GC doing more work, and will leave barriers turned on for longer.

Do we have evidence that GC slices are a problem during page load?  I expect that we do.

Another possibility would be to look at making GCs less likely to start during page load by increasing heap thresholds while this is happening.

Comment 3

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

GC and especially CC collecting objects from previous page during page load does show up in profiles.