From 35d98330f2629d7ad2b1f93d9e4d83fa2038611d Mon Sep 17 00:00:00 2001
From: corey-derochie-amd
 <161367113+corey-derochie-amd@users.noreply.github.com>
Date: Tue, 8 Oct 2024 10:20:55 -0600
Subject: [PATCH] Only set `minNchannels` if we are actually using MSCCL,
 checked using `comm->mscclCompatible`. (#1337)

[ROCm/rccl commit: c11f6b15317238cf9503616e781a90afe60e74b3]
---
 projects/rccl/src/graph/connect.cc | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/projects/rccl/src/graph/connect.cc b/projects/rccl/src/graph/connect.cc
index 3191028688..1c1d45690f 100644
--- a/projects/rccl/src/graph/connect.cc
+++ b/projects/rccl/src/graph/connect.cc
@@ -691,7 +691,9 @@ ncclResult_t ncclTopoPostset(struct ncclComm* comm, int* firstRanks, int* treePa
   if (mscclEnabled() && (comm->topo->mscclEnabled || mscclForceEnabled())) {
     int mscclNumChannelsRequired = maxNchannels;
     mscclSchedulerInit(comm, &mscclNumChannelsRequired);
-    minNchannels = std::max(minNchannels, mscclNumChannelsRequired);
+    if (comm->mscclCompatible) {
+      minNchannels = std::max(minNchannels, mscclNumChannelsRequired);
+    }
   }
 
   // Honor NCCL_MIN_NRINGS/NCCL_MAX_NRINGS.