Tune NVSHMEM NIC-to-PE Mapping

Purpose

Produce a reproducible recommendation from the target node's actual GPU/NIC topology. Do not promise a performance improvement; present the mapping as a topology-informed starting point that must be validated.

Requirements

• Use an allocated target compute node with visible GPUs and RDMA devices; do not use login-node topology as evidence.
• Make nvidia-smi and /sys/class/infiniband readable on that node. If /sys is unavailable, make ibv_devinfo available or provide equivalent per-port evidence.
• Provide the NVSHMEM installation prefix, make nvshmem-info available on the target node, or supply the installed NVSHMEM version explicitly.
• Use the bundled read-only collector when possible. It requires no API keys, credentials, package installation, or writable filesystem access.

Inputs

Resolve every required input before emitting exact exports. If values from different sources conflict, identify the conflict and request clarification rather than selecting a value silently.

Required inputs