commit ae7269f134ede59c815b22c1fd042b26bab96b7a
author Michael Lippautz <mlippautz@chromium.org> Wed Feb 21 17:26:11 2024
committer Chromium LUCI CQ <chromium-scoped@luci-project-accounts.iam.gserviceaccount.com> Wed Feb 21 17:26:11 2024
tree f661c2b1984608fc091feb5869d0a4fba198a103
parent dda2878a53ce4026058e14714f262ecac112dcc4

heap: Remove Blink's GCTaskRunner

Note: This change does not affect production semantics of garbage
collection.

Safepoint support was necessary in the initial implementation of
Oilpan (anno 2015) to run stack-less GCs in a timely fashion. The
safepoint mechanism uses task observers and as such hooks into _every_
task that was executed on the main thread. This completely bypassed
the scheduler and any heuristics it may have to meet deadlines.

These days the GCs are all triggered through unified heap in V8.
Asynchronous GCs (== stack-less GC) are implemented via scheduling
non-nestable tasks through `PostNonNestableTask()` for GC
finalizations.

The safepoint hook was still used to perform stack-less GCs after JS
`gc()` intrinsic calls in testing scenarios. These days these are
better written using `asyncGC()` (in web tests) and using the advanced
options for the `gc()` intrinsic that allow for awaitable async GC
otherwise (using `await gc({type: 'major', execution: 'async'})`).

A small side effect of this is that we also make prod faster by
removing a task observer that was otherwise always present.

Change-Id: I45bf0e826b07423c301fd242f38ed7a9e400667c
Bug: b/325123755, b/326091483, b/326192741
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5310195
Reviewed-by: Omer Katz <omerkatz@chromium.org>
Commit-Queue: Michael Lippautz <mlippautz@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1263406}