1900324 - Don't put alloc sites into the active list until they reach the attention threshold

Status: RESOLVED FIXED

(Core :: JavaScript: GC, enhancement, P1)

Description

[Jon Coppeard (:jonco)]

We maintain a list of active alloc sites which are processed at the end of a nursery collection. Any sites where the number of nursery allocations reaches the attention threshold are considered for pretenuring.

Currently we put alloc sites into this list the first time an allocation is made using that site since the last nursery collection. Instead we can delay this until the number of allocations reaches the attention threshold. This reduces the size of the list and hence the amount of processing needed at the next nursery collection.

This changes the meaning of the site's allocation and tenured count fields, since these no longer related to the time since the last collection but to the time since the site was last processed. The only effect this has on pretenuring is to make it more likely to pretenure some sites with very low allocation frequency which would have been ignored before.

Comment 1

[Jon Coppeard (:jonco)]

Attachment: Bug 1900324 - Don't put alloc sites into the active list until they reach the attention threshold r?jandem

Comment 2

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/e49d2ac030ba
Don't put alloc sites into the active list until they reach the attention threshold r=jandem

Comment 3

[Sandor Molnar[:smolnar]]

https://hg.mozilla.org/mozilla-central/rev/e49d2ac030ba