diff --git a/apps/nccl/src/allreduce.hpp b/apps/nccl/src/allreduce.hpp
index 76674ba..7a2cd4a 100644
--- a/apps/nccl/src/allreduce.hpp
+++ b/apps/nccl/src/allreduce.hpp
@@ -368,7 +368,10 @@ __global__ void __launch_bounds__(512, 1)
   const size_t chanOffset = nPeer * blockIdx.x;
   // assume (nelems * sizeof(T)) is divisible by (16 * worldSize)
   const size_t nInt4 = nelems * sizeof(T) / sizeof(int4);
-  const size_t nInt4PerRank = nInt4 / worldSize;
+  size_t nInt4PerRank = nInt4 / worldSize;
+  if (nInt4 % worldSize)
+        nInt4PerRank = nInt4PerRank + 1;
+
   auto smChans = smChannels + chanOffset;
   auto smOutChans = smOutChannels + chanOffset;