AllReduce/AllGather scaling in ASTRA-sim across torus vs switch topologies on the analytical + ns-3 backends — latency-bound vs bandwidth-bound over message size and node count. Reproducible Docker/Chakra harness + write-up.

hpc torus ns-3 allreduce roofline network-simulation distributed-ml collective-communication ml-systems astra-sim allgather gpu-interconnect

• Updated Jun 10, 2026
• Python