Fix incorrect net counting (#339)

* Fix incorrect net counting * Add comments
2021-04-05 12:21:57 -07:00
parent 1d2946ee4b
commit 17491c918e
2 changed files with 4 additions and 2 deletions
@@ -604,7 +604,8 @@ ncclResult_t initTransportsRank_3(struct ncclComm* comm, struct allGather3Data_t
  // count NETs used by ring
  int nNets = 0;
  int nets[MAXCHANNELS*2];
-  for (int i = 0; i < ringGraph.nChannels; i++) {
+  // do not count NETs in case of single node, i.e comm->topo->nodes[GPU].count == comm->topo->nRanks
+  for (int i = 0; comm->topo->nodes[GPU].count != comm->topo->nRanks && i < ringGraph.nChannels; i++) {
    for (int j = 0; j < 2; j++) {
      int k;
      for (k = 0; k < nNets; k++)