acs disable gpu p2p nccl
2 articles
PCIe Switch Topologies for 8-GPU Servers: P2P, ACS, IOMMU
How PCIe switches, root complexes, ACS and the IOMMU decide GPU peer-to-peer paths in 8-GPU PCIe servers, and what that means for NCCL.
October 28, 2026• 15 min read
pcie switch gpu server topologynvidia-smi topo -m pix pxb phbacs disable gpu p2p nccl
GPU Server BIOS and OS Baseline: IOMMU, ACS, Persistence
A sourced BIOS and Linux baseline for GPU servers: IOMMU pass-through, ACS, Above 4G/BAR, C-states, NUMA, persistence daemon, Fabric Manager, verifier.
October 28, 2026• 14 min read
gpu server bios settingsiommu pass-through gpu peer to peeracs disable gpu p2p nccl