Restore zero copy writes on Python 3.12.9+/3.13.2+

[bdraco]

TODO

• Hold until 3.13.2 release day: Tuesday, 2025-02-04
• Wait for GitHub to update 3.13 runners to 3.13.2
• Re-run benchmarks
• If benchmarks show the perf regression is fixed, this should be good to move forward and do a new release

What do these changes do?

Restore zero copy support on Python 3.12.9+/3.13.2+ (unreleased at this time)
CVE-2024-12254 aka GHSA-fw89-6wjj-8j95 is fixed on these Python versions

Are there changes in behavior for the user?

The performance regression introduced by disabling zero copy writes in #10125 will be resolved

The relevant benchmarks (keep in mind we are benchmarking disabling zero copy writes), and this PR seeks to restore the performance:

test_one_hundred_get_requests_with_1024_chunked_payload +3% (writelines is a bit worse for tiny payloads)
test_one_hundred_get_requests_with_512kib_chunked_payload -21% (writelines is a lot better for large payloads)
test_one_hundred_get_requests_with_30000_chunked_payload -4% (writelines is a slightly better for medium size payloads)

Since we already have to branch here, I also added MIN_PAYLOAD_FOR_WRITELINES to 2048 to ensure we no longer take the 3% performance hit for writelines with small payloads

[codspeed-hq]

CodSpeed Performance Report

Merging #10137 will improve performances by 18.02%

_{Comparing restore_zero_copy (9645236) with master (8bf5d4d)}

Summary

⚡ 1 improvements
✅ 46 untouched benchmarks

Benchmarks breakdown

	Benchmark	BASE	HEAD	Change
⚡	test_one_hundred_get_requests_with_512kib_chunked_payload[pyloop]	222.4 ms	188.4 ms	+18.02%

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 98.76%. Comparing base (8bf5d4d) to head (9645236).
Report is 2 commits behind head on master.

✅ All tests successful. No failed tests found.

Additional details and impacted files

@@            Coverage Diff             @@
##           master   #10137      +/-   ##
==========================================
- Coverage   98.76%   98.76%   -0.01%     
==========================================
  Files         122      122              
  Lines       37048    37123      +75     
  Branches     2042     2044       +2     
==========================================
+ Hits        36590    36664      +74     
- Misses        318      319       +1     
  Partials      140      140              

Flag	Coverage Δ
CI-GHA	98.65% <100.00%> (+<0.01%)	⬆️
OS-Linux	98.33% <100.00%> (+<0.01%)	⬆️
OS-Windows	96.25% <100.00%> (+0.01%)	⬆️
OS-macOS	97.45% <100.00%> (+0.01%)	⬆️
Py-3.10.11	97.34% <100.00%> (+0.01%)	⬆️
Py-3.10.16	97.91% <100.00%> (+<0.01%)	⬆️
Py-3.11.11	98.00% <100.00%> (+<0.01%)	⬆️
Py-3.11.9	97.42% <100.00%> (+0.01%)	⬆️
Py-3.12.8	98.43% <100.00%> (+<0.01%)	⬆️
Py-3.13.1	98.42% <100.00%> (+<0.01%)	⬆️
Py-3.9.13	97.23% <100.00%> (+0.01%)	⬆️
Py-3.9.21	97.79% <100.00%> (+<0.01%)	⬆️
Py-pypy7.3.16	97.38% <100.00%> (+0.01%)	⬆️
VM-macos	97.45% <100.00%> (+0.01%)	⬆️
VM-ubuntu	98.33% <100.00%> (+<0.01%)	⬆️
VM-windows	96.25% <100.00%> (+0.01%)	⬆️

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[bdraco]

almost released https://github.com/actions/python-versions/releases/tag/3.13.2-13149511920

[bdraco]

as soon as actions/python-versions#331 merges we can re-run

[webknjaz]

It's merged!

[bdraco]

Looks like we are still getting 3.13.1

Successfully set up CPython (3.13.1)

[bdraco]

There we go

Merging #10137 will improve performances by 18.02%

[patchback]

Backport to 3.11: 💔 cherry-picking failed — conflicts found

❌ Failed to cleanly apply 25c7f23 on top of patchback/backports/3.11/25c7f2382be9b5e03b8d22671f36a2f6fb07221a/pr-10137

Backporting merged PR #10137 into master

1. Ensure you have a local repo clone of your fork. Unless you cloned it
   from the upstream, this would be your origin remote.
2. Make sure you have an upstream repo added as a remote too. In these
   instructions you'll refer to it by the name upstream. If you don't
   have it, here's how you can add it:

   $ git remote add upstream https://github.com/aio-libs/aiohttp.git

3. Ensure you have the latest copy of upstream and prepare a branch
   that will hold the backported code:

   $ git fetch upstream
   $ git checkout -b patchback/backports/3.11/25c7f2382be9b5e03b8d22671f36a2f6fb07221a/pr-10137 upstream/3.11

4. Now, cherry-pick PR Restore zero copy writes on Python 3.12.9+/3.13.2+ #10137 contents into that branch:

   $ git cherry-pick -x 25c7f2382be9b5e03b8d22671f36a2f6fb07221a

   If it'll yell at you with something like fatal: Commit 25c7f2382be9b5e03b8d22671f36a2f6fb07221a is a merge but no -m option was given., add -m 1 as follows instead:

   $ git cherry-pick -m1 -x 25c7f2382be9b5e03b8d22671f36a2f6fb07221a

5. At this point, you'll probably encounter some merge conflicts. You must
   resolve them in to preserve the patch from PR Restore zero copy writes on Python 3.12.9+/3.13.2+ #10137 as close to the
   original as possible.
6. Push this branch to your fork on GitHub:

   $ git push origin patchback/backports/3.11/25c7f2382be9b5e03b8d22671f36a2f6fb07221a/pr-10137

7. Create a PR, ensure that the CI is green. If it's not — update it so that
   the tests and any other checks pass. This is it!
   Now relax and wait for the maintainers to process your pull request
   when they have some cycles to do reviews. Don't worry — they'll tell you if
   any improvements are necessary when the time comes!

🤖 @patchback
I'm built with octomachinery and
my source is open — https://github.com/sanitizers/patchback-github-app.

[patchback]

Backport to 3.12: 💔 cherry-picking failed — conflicts found

❌ Failed to cleanly apply 25c7f23 on top of patchback/backports/3.12/25c7f2382be9b5e03b8d22671f36a2f6fb07221a/pr-10137

Backporting merged PR #10137 into master

1. Ensure you have a local repo clone of your fork. Unless you cloned it
   from the upstream, this would be your origin remote.
2. Make sure you have an upstream repo added as a remote too. In these
   instructions you'll refer to it by the name upstream. If you don't
   have it, here's how you can add it:

   $ git remote add upstream https://github.com/aio-libs/aiohttp.git

3. Ensure you have the latest copy of upstream and prepare a branch
   that will hold the backported code:

   $ git fetch upstream
   $ git checkout -b patchback/backports/3.12/25c7f2382be9b5e03b8d22671f36a2f6fb07221a/pr-10137 upstream/3.12

4. Now, cherry-pick PR Restore zero copy writes on Python 3.12.9+/3.13.2+ #10137 contents into that branch:

   $ git cherry-pick -x 25c7f2382be9b5e03b8d22671f36a2f6fb07221a

   If it'll yell at you with something like fatal: Commit 25c7f2382be9b5e03b8d22671f36a2f6fb07221a is a merge but no -m option was given., add -m 1 as follows instead:

   $ git cherry-pick -m1 -x 25c7f2382be9b5e03b8d22671f36a2f6fb07221a

5. At this point, you'll probably encounter some merge conflicts. You must
   resolve them in to preserve the patch from PR Restore zero copy writes on Python 3.12.9+/3.13.2+ #10137 as close to the
   original as possible.
6. Push this branch to your fork on GitHub:

   $ git push origin patchback/backports/3.12/25c7f2382be9b5e03b8d22671f36a2f6fb07221a/pr-10137

7. Create a PR, ensure that the CI is green. If it's not — update it so that
   the tests and any other checks pass. This is it!
   Now relax and wait for the maintainers to process your pull request
   when they have some cycles to do reviews. Don't worry — they'll tell you if
   any improvements are necessary when the time comes!

🤖 @patchback
I'm built with octomachinery and
my source is open — https://github.com/sanitizers/patchback-github-app.