[Feature]: Add uccl as kvconnect provide

[lengrongfu]

🚀 The feature, motivation and pitch

According to uccl benchmark, uccl excellent performance in all aspects. https://uccl-project.github.io/posts/kv-transfer-engine/

Alternatives

No response

Additional context

No response

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[lengrongfu]

/assign

[robertgshaw2-redhat]

is UCCL available as a backend for NIXL?

[lengrongfu]

Can developer a NIXL plugin use UCCL to use p2p capability, However, if we want to use the all2all capability of UCCL, we still need to integrate it separately.
uccl-project/uccl#38

[praveingk]

@robertgshaw2-redhat UCCL backend for NIXL is under development, praveingk/nixl-uccl#1 . I would say most of the plumbing is done, I am hardening it, and fixing some loose ends.

[lengrongfu]

NIXL-ucll solves the problem of using UCCL for P2P communication, but the remaining problem is to use UCCL's all2all capability.

[praveingk]

@lengrongfu UCCL backend support for NIXL : ai-dynamo/nixl#895 . Validated with vLLM's nixl_connector