Inference: Do not let prompt tokens return from the engine, unless requested#5918
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sidsingh-nvidia merged 6 commits intoJul 23, 2026
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Signed-off-by: Siddharth Singh <sidsingh@nvidia.com>
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kvareddy
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Jul 21, 2026
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Cover the new DynamicInferenceRequest.serialize() drop/keep contract from PR NVIDIA#5918: prompt_length is always reported (needed for usage.prompt_tokens), the prompt_tokens tensor is dropped from the wire payload unless SamplingParams.return_prompt_tokens=True, self.prompt_tokens is restored on the local instance, the routing_indices shape check still uses the saved prompt_len when self.prompt_tokens is temporarily nulled, and the None-prompt edge case does not crash. Signed-off-by: shanmugamr1992 <shanmugamr@nvidia.com> Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
sidsingh-nvidia
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July 21, 2026 22:17
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Jul 21, 2026
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What does this PR do?
Transmitting prompt tokens, especially in agentic-RL at high ctx lengths, can be costly. This PR makes it such that prompt tokens are removed from the request object before serialization by default, unless those tokens are explicitly requested by the user. Benefits have been observed with cross-node DP
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