From 9594bbee3b9caaa4d7707641eab52e57a1b7f732 Mon Sep 17 00:00:00 2001
From: Wenkai Du <43822138+wenkaidu@users.noreply.github.com>
Date: Tue, 29 Nov 2022 13:57:10 -0800
Subject: [PATCH] Adjust P2P channels on Intel platform (#653)

---
 src/graph/paths.cc | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/src/graph/paths.cc b/src/graph/paths.cc
index bf95319b22..b0de0dc991 100644
--- a/src/graph/paths.cc
+++ b/src/graph/paths.cc
@@ -814,7 +814,13 @@ ncclResult_t ncclTopoComputeP2pChannels(struct ncclComm* comm) {
     }
   }
 
-  if (comm->topo->nodes[GPU].count == comm->topo->nRanks && (comm->topo->type & RCCL_TOPO_4P2H_ROME) && !(comm->topo->type & RCCL_TOPO_GDR_ALL) && !(comm->topo->type & RCCL_TOPO_XGMI_ALL)) {
+  int arch, vendor, model;
+  NCCLCHECK(ncclTopoCpuType(comm->topo, &arch, &vendor, &model));
+  if (arch == NCCL_TOPO_CPU_ARCH_X86 || vendor == NCCL_TOPO_CPU_VENDOR_INTEL) {
+    // Adjust P2P channels on Intel platform
+    comm->p2pnChannelsPerPeer = 1;
+    comm->p2pnChannels = 2;
+  } else if (comm->topo->nodes[GPU].count == comm->topo->nRanks && (comm->topo->type & RCCL_TOPO_4P2H_ROME) && !(comm->topo->type & RCCL_TOPO_GDR_ALL) && !(comm->topo->type & RCCL_TOPO_XGMI_ALL)) {
     // Adjust P2P channels on Rome
     comm->p2pnChannelsPerPeer = 2;
     comm->p2pnChannels = 2;