[PD][NixlPush] Skip extra `add_remote_agent` step in D->P handshake (#49345)
Signed-off-by: NickLucche <nicolo.lucchesi@mistral.ai>
Nicolò Lucchesi committed
Jul 28, 2026 at 14:57 UTC
98e91a9600eb75b2de14ef27f13b10088d1a1279
2 files changed
+6
-3
vllm/distributed/kv_transfer/kv_connector/v1/nixl/base_worker.py
+2
-1
@@ -700,8 +700,9 @@ class NixlBaseConnectorWorker:
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)
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setup_agent_time = time.perf_counter()
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logger.debug(
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- "NIXL handshake: add agent took: %s",
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+ "NIXL handshake: add agent took: %s (notif_agents_only=%s)",
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setup_agent_time - got_metadata_time,
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+ notif_agents_only,
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)
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remote_ranks = (remote_pp_rank, remote_rank)
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remote_rank_to_agent_name[remote_ranks] = remote_agent_name
vllm/distributed/kv_transfer/kv_connector/v1/nixl/push_worker.py
+4
-2
@@ -299,8 +299,10 @@ class NixlPushConnectorWorker(NixlBaseConnectorWorker):
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reg_data["remote_port"],
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reg_data["remote_tp_size"],
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pp_size=remote_pp_size,
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- # D never addresses P memory in push mode; just load P's agents.
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- notif_agents_only=remote_pp_size > 1,
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+ # D only ever sends PUSH_REG notifs to P and never reads or writes
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+ # P's memory in push mode, so it never needs the transfer
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+ # descriptors set up by the full add_remote_agent path.
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+ notif_agents_only=True,
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)
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if fut is None:
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self._do_send_reg_notif(req_id, reg_data)