diff --git a/wddm/queue.cpp b/wddm/queue.cpp
index c10a034705..44658819cb 100644
--- a/wddm/queue.cpp
+++ b/wddm/queue.cpp
@@ -499,12 +499,12 @@ bool ComputeQueue::UpdateScratch(hsa_kernel_dispatch_packet_t *packet, bool wave
   const uint64_t size_per_thread = AlignUp(packet->private_segment_size,
                                   scratch_mem_alignment_size_ / lanes_per_wave);
 
-  scratch_size_per_wave_ = size_per_thread * lanes_per_wave;
-
   uint64_t groups = CalcDispatchGroups(packet);
   uint64_t waves_per_group = CalcDispatchWavesPerGroup(packet, wave32);
 
-  dispatch_waves_ = groups * waves_per_group;
+  // For packet batching, the maximum value must be used to fit all packets.
+  scratch_size_per_wave_ = std::max(size_per_thread * lanes_per_wave, scratch_size_per_wave_);
+  dispatch_waves_ = std::max(groups * waves_per_group, dispatch_waves_);
 
   const uint64_t max_scratch_size = scratch_size_per_wave_ * max_scratch_waves_;
   const uint64_t dispatch_size = scratch_size_per_wave_ * dispatch_waves_;