1716531 - Don't pay attention to low volume allocation sites

Status: RESOLVED FIXED

(Core :: JavaScript: GC, enhancement, P3)

Description

[Jon Coppeard (:jonco)]

Currently we process allocation sites that have 100 allocations in the nursery. This threshold is there to ensure there is enough data to reliably infer the lifetime of these allocations.

However this is still a low threshold at which to pretenure a site. In practice we may end up pretenuring many low volume allocation sites which could result in more garbage surviving nursery collections and increasing major GC frequency.

The main use case for allocation sites is to ensure high volume allocation sites that are long lived don't get allocated in the nursery. We can increase this threshold substantially without affecting that, and this should lead to less garbage being kept alive.

Comment 1

[Jon Coppeard (:jonco)]

Attachment: Bug 1716531 - Increase the allocation threshold at which we pay attention to allocation sites r?jandem

Comment 2

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/10a8666b8eae
Increase the allocation threshold at which we pay attention to allocation sites r=jandem

Comment 3

[Cosmin Sabou [:CosminS]]

https://hg.mozilla.org/mozilla-central/rev/10a8666b8eae