1866451 - Limit number of parallel IonFreeTasks

Status: RESOLVED FIXED

(Core :: JavaScript Engine: JIT, task)

Description

[Jan de Mooij [:jandem]]

These are low-priority tasks (nothing is blocked on them) that are just freeing memory, so if we run multiple of these tasks in parallel it's more likely that we hit jemalloc lock contention issues. This would also block higher-priority tasks if all threads are occupied.

Similar to the source compression tasks, I think we should limit these to one active task. After this we can also try batching more compilation tasks into a single IonFreeTask.

The latest perf comparison has some medium-confidence improvements for sp3 sub tests, so I think it's worth trying:

https://treeherder.mozilla.org/perfherder/comparesubtest?originalProject=try&newProject=try&newRevision=4ad40379e2af5417c16e57dc1bb4fb705456640e&originalSignature=4586009&newSignature=4586009&framework=13&application=firefox&originalRevision=2bab0fb91785ee42d2857fe4c52be54eba15c1ef&page=1

Comment 1

[Jan de Mooij [:jandem]]

Attachment: Bug 1866451 - Limit number of parallel IonFreeTasks to 1. r?jonco!

Comment 2

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/9f6a51cc4271
Limit number of parallel IonFreeTasks to 1. r=jonco

Comment 3

[Iulian Moraru]

https://hg.mozilla.org/mozilla-central/rev/9f6a51cc4271