731783 - GC: Eliminate per-compartment barrier marker

Status: RESOLVED FIXED

(Core :: JavaScript Engine, defect)

Description

[Bill McCloskey [inactive unless it's an emergency] (:billm)]

Attachment: patch

We don't need this anymore since the runtime is now single-threaded.

I also fixed GCMarker::stop so that it releases memory that was allocated during the collection.

Comment 1

[Igor Bukanov]

Comment on attachment 601754 [details] [diff] [review]
patch

Review of attachment 601754 [details] [diff] [review]:
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Nice!

Comment 2

[Bill McCloskey [inactive unless it's an emergency] (:billm)]

Just so it's clear, this won't decrease memory usage by much at all. The stuff that we were pushing onto the per-compartment mark stack will now be pushed onto the per-runtime mark stack. But I guess that's a little better from a memshrink perspective because we have a memory reporter for the latter and not for the former.

Comment 3

[Nicholas Nethercote [inactive]]

> Just so it's clear, this won't decrease memory usage by much at all.

I clarified this with billm on IRC.  With heavy usage the MarkStack can grow a lot.  E.g. with MemBench it gets up to 2.8MB.  Prior to this patch, once grown it would never shrink again, but with this patch it will shrink back to 256KB.

Comment 4

[Bill McCloskey [inactive unless it's an emergency] (:billm)]

https://hg.mozilla.org/integration/mozilla-inbound/rev/fbdaf507dcb5

Comment 5

[Marco Bonardo [:mak]]

https://hg.mozilla.org/mozilla-central/rev/fbdaf507dcb5