Avoid scheduling the writer if it can finish synchronously

[bdraco]

What do these changes do?

python3.12 introduces eager_start for asyncio.Task, and in most cases writing the http request can be done synchronously because its a small amount of data and will never fill up the buffer causing the task to suspend. This means that the task never has to be scheduled on the event loop, and we avoid a call_soon to schedule the task, and we avoid a call_soon to cleanup the writer since its done right away.

Are there changes in behavior for the user?

requests will finish much faster in many cases

Is it a substantial burden for the maintainers to support this?

We have to maintain two branches until we only support python 3.12+ https://github.com/aio-libs/aiohttp/pull/8510/files#diff-720910fd022b9ba8b7ddf0cb446ce5e1afe443f4287ad26a1eb4dc4b5b5f4508R671. This should be minimal

Related issue number

Checklist

• I think the code is well written
• Unit tests for the changes exist
• Documentation reflects the changes
• If you provide code modification, please add yourself to CONTRIBUTORS.txt
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    Fixed issue with non-ascii contents in doctest text files
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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 97.63%. Comparing base (62173be) to head (aee6830).
Report is 919 commits behind head on master.

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #8510   +/-   ##
=======================================
  Coverage   97.62%   97.63%           
=======================================
  Files         107      107           
  Lines       33262    33293   +31     
  Branches     3905     3911    +6     
=======================================
+ Hits        32472    32505   +33     
+ Misses        571      570    -1     
+ Partials      219      218    -1     

Flag	Coverage Δ
CI-GHA	97.54% <97.50%> (+<0.01%)	⬆️
OS-Linux	97.21% <97.50%> (+<0.01%)	⬆️
OS-Windows	95.67% <97.50%> (+<0.01%)	⬆️
OS-macOS	96.87% <97.50%> (+<0.01%)	⬆️
Py-3.10.11	97.01% <90.00%> (-0.01%)	⬇️
Py-3.10.14	96.96% <90.00%> (-0.01%)	⬇️
Py-3.11.9	97.18% <90.00%> (-0.01%)	⬇️
Py-3.12.4	97.31% <95.00%> (+<0.01%)	⬆️
Py-3.8.10	95.43% <90.00%> (-0.01%)	⬇️
Py-3.8.18	96.85% <90.00%> (-0.01%)	⬇️
Py-3.9.13	96.99% <90.00%> (-0.01%)	⬇️
Py-3.9.19	96.95% <90.00%> (-0.01%)	⬇️
Py-pypy7.3.16	96.52% <90.00%> (-0.01%)	⬇️
VM-macos	96.87% <97.50%> (+<0.01%)	⬆️
VM-ubuntu	97.21% <97.50%> (+<0.01%)	⬆️
VM-windows	95.67% <97.50%> (+<0.01%)	⬆️

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[bdraco]

This one has been running fine on my 3.12 production and 3.11 test setups.

[patchback]

Backport to 3.10: 💔 cherry-picking failed — conflicts found

❌ Failed to cleanly apply 38fc33b on top of patchback/backports/3.10/38fc33b1a3b5630dcc36ff688695e448d741717d/pr-8510

Backporting merged PR #8510 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/3.10/38fc33b1a3b5630dcc36ff688695e448d741717d/pr-8510 upstream/3.10

4. Now, cherry-pick PR Avoid scheduling the writer if it can finish synchronously #8510 contents into that branch:

   $ git cherry-pick -x 38fc33b1a3b5630dcc36ff688695e448d741717d

   If it'll yell at you with something like fatal: Commit 38fc33b1a3b5630dcc36ff688695e448d741717d is a merge but no -m option was given., add -m 1 as follows instead:

   $ git cherry-pick -m1 -x 38fc33b1a3b5630dcc36ff688695e448d741717d

5. At this point, you'll probably encounter some merge conflicts. You must
   resolve them in to preserve the patch from PR Avoid scheduling the writer if it can finish synchronously #8510 as close to the
   original as possible.
6. Push this branch to your fork on GitHub:

   $ git push origin patchback/backports/3.10/38fc33b1a3b5630dcc36ff688695e448d741717d/pr-8510

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.

[bdraco]

thanks