[Bugfix]fix_mulit_connector_bug

[baxingpiaochong]

What this PR does / why we need it?

When using multi connector, the multi connector does not define get_finished_count, which will cause the kv cache to be released

Does this PR introduce any user-facing change?

How was this patch tested?

• vLLM version: v0.11.0rc3
• vLLM main: https://github.com/vllm-project/vllm/commit/v0.11.0

[github-actions]

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[gemini-code-assist]

Code Review

This pull request aims to fix a bug in the multi-connector logic. It adjusts how the finished count is determined and adds logic to handle requests that don't require data transfer. While the intent seems correct, there's a critical issue in the implementation regarding duplicated and potentially incorrect method logic that needs to be addressed.

[gemini-code-assist]

The newly added method add_not_transfer_request is identical to the update_done_task_count method as shown in the diff at lines 79-81. This code duplication is problematic.

• If they are meant to be identical, please remove one to avoid confusion and maintenance overhead.
• If update_done_task_count should have more complex logic (as is often the case for such functions and as suggested by the full file context), then this change might be introducing a critical bug by simplifying it or the diff is misleading.

Please resolve this ambiguity. The current state is confusing and potentially incorrect.

[github-actions]

This pull request has conflicts, please resolve those before we can evaluate the pull request.