gaaclarke 3c31a896c8 [Impeller] Started using a pool for HostBuffers. (flutter/engine#44081)
This removes ~792 MB/s of allocation when scrolling around the Gallery
((358 MB - 226 MB) * 6).

## before
<img width="1337" alt="Screenshot 2023-07-27 at 1 48 57 PM"
src="https://github.com/flutter/engine/assets/30870216/d320c2da-c333-40b7-9326-c9b69e5ff462">

## after
<img width="1391" alt="Screenshot 2023-07-27 at 1 36 35 PM"
src="https://github.com/flutter/engine/assets/30870216/e3314a03-8691-4766-9989-aef112703384">


## Pre-launch Checklist

- [x] I read the [Contributor Guide] and followed the process outlined
there for submitting PRs.
- [x] I read the [Tree Hygiene] wiki page, which explains my
responsibilities.
- [x] I read and followed the [Flutter Style Guide] and the [C++,
Objective-C, Java style guides].
- [x] I listed at least one issue that this PR fixes in the description
above.
- [ ] I added new tests to check the change I am making or feature I am
adding, or Hixie said the PR is test-exempt. See [testing the engine]
for instructions on writing and running engine tests.
- [x] I updated/added relevant documentation (doc comments with `///`).
- [x] I signed the [CLA].
- [x] All existing and new tests are passing.

If you need help, consider asking for advice on the #hackers-new channel
on [Discord].

<!-- Links -->
[Contributor Guide]:
https://github.com/flutter/flutter/wiki/Tree-hygiene#overview
[Tree Hygiene]: https://github.com/flutter/flutter/wiki/Tree-hygiene
[Flutter Style Guide]:
https://github.com/flutter/flutter/wiki/Style-guide-for-Flutter-repo
[C++, Objective-C, Java style guides]:
https://github.com/flutter/engine/blob/main/CONTRIBUTING.md#style
[testing the engine]:
https://github.com/flutter/flutter/wiki/Testing-the-engine
[CLA]: https://cla.developers.google.com/
[flutter/tests]: https://github.com/flutter/tests
[breaking change policy]:
https://github.com/flutter/flutter/wiki/Tree-hygiene#handling-breaking-changes
[Discord]: https://github.com/flutter/flutter/wiki/Chat

---------

Co-authored-by: Jonah Williams <jonahwilliams@google.com>
2023-08-01 09:54:14 -07:00
..