flashinfer.comm.probe_ulysses_rank_topology

flashinfer.comm.probe_ulysses_rank_topology(device: device | str | int | None, rank: int) → UlyssesRankTopology

Probe this rank’s GPU identity and its P2P/NVLink reachability to every other CUDA device visible to this process.

Never raises: the whole probe (including hostname and device resolution) runs inside an exception envelope, so any failure lands in probe_error and the (conservative) decision layer falls back to NCCL.