Address high cpu usage with AWSCRTHTTPClient

[jonathan343]

Summary

This PR integrates with the new aync CRT APIs introduced in awslabs/aws-crt-python#658 with the goal of addressing the high CPU usage reported in awslabs/aws-sdk-python#11.

The changes in this PR have been tested and successfully reduce CPU usage for examples such as the bidirectional nova_sonic.py. This change will be available in a new versions of smithy-http and aws-sdk-bedrock-runtime with no changes to the user experience.

Testing

1. Checkout this PR locally
   • gh pr checkout 573
2. Create a activate a Python virtual environment
   • uv venv && source .venv/bin/activate
3. Install workspace dependencies
   • make install
4. Install bedrock runtime sdk client
   • uv pip install aws-sdk-bedrock-runtime psutil pyaudio rx
5. Download the monitor_cpu.py and bidirection.py test scripts.
6. Run python monitor_cpu.py bidirection.py

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[jonathan343]

Note

Setting awscrt v0.28.2 is necessary since we need the change added in awslabs/aws-crt-python#688. Also, this was previously unbounded which has been fine for now, but constraining it to ~=0.28.2 is much safer for customers

[JordonPhillips]

Why this number in particular?

[jonathan343]

It was a common buffer size I'd come across, however, I do see our default value is -1 which will read all available data at once.

smithy-python/packages/smithy-core/src/smithy_core/aio/interfaces/__init__.py

Lines 23 to 27 in d9b9e2b

	@runtime_checkable
	class AsyncByteStream(Protocol):
	"""A file-like object with an async read method."""
	async def read(self, size: int = -1) -> bytes: ...

Do you prefer going with the default?

[jonathan343]

Updated to use the default in 02e3e20. Let me know what you think

[JordonPhillips]

The default is for the protocol - when you call .read on a file-like object, for instance, it just reads everything. We should read in chunks, i was just wondering why that size in particular. Just make it a constant or something that's configurable on the crt client and we'll be good.

[JordonPhillips]

See response to other comment - we should still limit how much we read at a time from a file-like object, I just wanted to know why that number.