Minimal change to push back to dofn generating output if the sdk is producing faster than runner is consuming.

[scwhittle]

This is just a WIP, I plan on creating a queue that also supports byte limits and using that along with higher element limits for both this send queue and the receive queues which are currently 10 elements per process_bundle_instruction.

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[gemini-code-assist]

Summary of Changes

Hello, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request introduces a capacity constraint on the data transmission queue within the gRPC data channel. By limiting the queue size, the system can better manage backpressure when the SDK produces data faster than the runner can consume it, preventing unbounded memory growth.

Highlights

• Queue Capacity Limit: Updated the _to_send queue in _GrpcDataChannel to enforce a maximum size of 10 elements.

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[gemini-code-assist]

Code Review

This pull request introduces a fixed size for the _to_send queue in the _GrpcDataChannel class. Feedback suggests that the hardcoded maxsize=10 should be made configurable to avoid potential performance bottlenecks in high-throughput scenarios and notes a discrepancy between the PR description and the implementation of the receive queue size.

[github-actions]

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R: @tvalentyn for label python.

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[tvalentyn]

thanks, marking as draft for now

[tvalentyn]

waiting on author