1472495 - Stop reporting script preloader mmapped cache as explicit memory

Status: RESOLVED FIXED

(Core :: XPConnect, enhancement, P2)

Description

[Kris Maglione [:kmag]]

We currently report the memory mapped script loader cache file as explicit non-heap memory. That's accurate, but it's also misleading, since it's shared among processes.

In particular, it's problematic for the AWSY base content explicit report, since it shows up there even though it's not per-content-process memory (which is what that report is supposed to track). That's going to become more of an issue in the future, since we're probably going to starting more shared JS runtime data to that file, which will make our actual per-content-process memory consumption go down, but will make the size of that file go up.

Comment 1

[Kris Maglione [:kmag]]

Attachment: Bug 1472495: Don't report shared memmapped cache as explicit memory.

Review commit: https://reviewboard.mozilla.org/r/254116/diff/#index_header
See other reviews: https://reviewboard.mozilla.org/r/254116/

Comment 2

[Eric Rahm [:erahm]]

Comment on attachment 8989028 [details]
Bug 1472495: Don't report shared memmapped cache as explicit memory.

https://reviewboard.mozilla.org/r/254116/#review261136

::: js/xpconnect/loader/ScriptPreloader.cpp:93
(Diff revision 1)
>          "explicit/script-preloader/heap/other", KIND_HEAP, UNITS_BYTES,
>          ShallowHeapSizeOfIncludingThis(MallocSizeOf),
>          "Memory used by the script cache service itself.");
>  
>      MOZ_COLLECT_REPORT(
> -        "explicit/script-preloader/non-heap/memmapped-cache", KIND_NONHEAP, UNITS_BYTES,
> +        "script-preloader-memmapped-cache", KIND_NONHEAP, UNITS_BYTES,

Can we keep reporting this as explicit in the parent? I'm okay w/ also reporting in the new location as well. I'd hate to stop reporting explicitly allocated shared memory altogether.

Comment 3

[Kris Maglione [:kmag]]

Comment on attachment 8989028 [details]
Bug 1472495: Don't report shared memmapped cache as explicit memory.

Review request updated; see interdiff: https://reviewboard.mozilla.org/r/254116/diff/1-2/

Comment 4

[Kris Maglione [:kmag]]

Comment on attachment 8989028 [details]
Bug 1472495: Don't report shared memmapped cache as explicit memory.

https://reviewboard.mozilla.org/r/254116/#review261136

> Can we keep reporting this as explicit in the parent? I'm okay w/ also reporting in the new location as well. I'd hate to stop reporting explicitly allocated shared memory altogether.

Yeah, that probably makes sense. I changed it to report as explicit in the parent and non-explicit everywhere else.

Comment 5

[Eric Rahm [:erahm]]

Comment on attachment 8989028 [details]
Bug 1472495: Don't report shared memmapped cache as explicit memory.

https://reviewboard.mozilla.org/r/254116/#review262344

Thanks for updating, looks good.

Comment 6

[Kris Maglione [:kmag]]

https://hg.mozilla.org/integration/mozilla-inbound/rev/6bf20a7a0b2a93bf69568aa487589725f08b68a8
Bug 1472495: Don't report shared memmapped cache as explicit memory. r=erahm

Comment 7

[Arthur Iakab [arthur_iakab]]

https://hg.mozilla.org/mozilla-central/rev/6bf20a7a0b2a