1437978 - Add memory reporting for scriptCountsMap

Status: RESOLVED FIXED

(Core :: JavaScript Engine: JIT, enhancement, P1)

Description

[Andrew McCreight [:mccr8]]

This takes up a decent chunk of memory, and it not covered by an existing memory reporter.

Here are some counts from a build with my patch applied.

Main process:
│  ├─────572,448 B (01.29%) ── script-counts-map

Content process with a simple page loaded:
│   ├────163,136 B (01.10%) ── script-counts-map

Other content process (maybe the preallocated process):
│  ├─────17,488 B (00.27%) ── script-counts-map

Comment 1

[Andrew McCreight [:mccr8]]

Attachment: Bug 1437978 - Add memory reporting for scriptCountsMap.

Review commit: https://reviewboard.mozilla.org/r/219946/diff/#index_header
See other reviews: https://reviewboard.mozilla.org/r/219946/

Comment 2

[Nicolas B. Pierron [:nbp]]

Comment on attachment 8950692 [details]
Bug 1437978 - Add memory reporting for scriptCountsMap.

https://reviewboard.mozilla.org/r/219946/#review225980

Comment 3

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/f86256e3a26e
Add memory reporting for scriptCountsMap. r=nbp

Comment 4

[Andreea Pavel [:apavel]]

https://hg.mozilla.org/mozilla-central/rev/f86256e3a26e

Comment 5

[Ionuț Goldan [:igoldan]]

Performance improvements win! \o/

== Change summary for alert #11572 (as of Wed, 14 Feb 2018 19:29:19 GMT) ==

Improvements:

  4%  Heap Unclassified windows7-32 opt stylo     36,317,937.73 -> 35,006,936.98
  4%  Heap Unclassified windows7-32 pgo stylo     36,305,785.93 -> 35,004,814.44
  3%  Heap Unclassified windows10-64 opt stylo    43,348,563.94 -> 41,859,718.92
  3%  Heap Unclassified windows10-64 pgo stylo    43,228,413.94 -> 41,853,528.84
  2%  Heap Unclassified linux64 opt stylo         58,429,303.97 -> 57,125,628.30

For up to date results, see: https://treeherder.mozilla.org/perf.html#/alerts?id=11572

Comment 6

[Jan de Mooij [:jandem]]

If scriptCountsMap accounted for 3-4% of heap-unclassified (> 1 MB) I think we should strongly consider purging it on shrinking GCs...

Comment 7

[Nicolas B. Pierron [:nbp]]

(In reply to Jan de Mooij [:jandem] from comment #6)
> If scriptCountsMap accounted for 3-4% of heap-unclassified (> 1 MB) I think
> we should strongly consider purging it on shrinking GCs...

I agree, and on a similar note, there is Bug 1398738.

And I will also note that we should be careful not to trash code coverage information, when we are explicitly running Firefox to collect coverage results.