1196109 - keep memory allocation for mixed input channel pointer array

Status: RESOLVED FIXED

(Core :: Web Audio, defect)

Description

[Karl Tomlinson (:karlt)]

Keeping a chunk for AudioNodeStream input saves on memory allocations for the channel pointer arrays and can sometimes mean that an input buffer can be reused without reallocation for mixing in the next iteration.

Comment 1

[Karl Tomlinson (:karlt)]

Attachment: keep memory allocation for mixed input channel pointer array

This saves about 10% on simple gain and upmix/downmix benchmarks but some of
the benefit in the benchmarks depends on (and is addition to the benefits
from) bug 1196108.

Comment 2

[Karl Tomlinson (:karlt)]

Attachment: keep memory allocation for mixed input channel pointer array

This version does the release logic in AudioChunk::ReleaseBufferIfShared()
to support bug 1197028 also.

The length of the channel pointer arrays are now set to zero to make it clear
that the pointers are no longer safe to use.

Comment 3

[Pulsebot]

https://hg.mozilla.org/integration/mozilla-inbound/rev/81b4ff538841

Comment 4

[Ryan VanderMeulen [:RyanVM]]

https://hg.mozilla.org/mozilla-central/rev/81b4ff538841