decrease buffer length and only form if child processes are present

m-a-d-n-e-s-s · Sep 12, 2024 · 30ce5ea · 30ce5ea
1 parent 96ac90e
commit 30ce5ea
Showing 1 changed file with 6 additions and 2 deletions.
diff --git a/src/madness/world/worldgop.h b/src/madness/world/worldgop.h
@@ -785,8 +785,12 @@ namespace madness {
  world_.mpi.binary_tree_info(0, parent, child0, child1);
  const std::size_t nelem_per_maxmsg = max_reducebcast_msg_size() / sizeof(T);
 
- auto buf0 = std::unique_ptr<T[]>(new T[nelem_per_maxmsg]);
- auto buf1 = std::unique_ptr<T[]>(new T[nelem_per_maxmsg]);
+ std::unique_ptr<T[]> buf0 = (child0 != -1)
+ ? std::unique_ptr<T[]>(new T[std::min(nelem_per_maxmsg,nelem)])
+ : nullptr;
+ std::unique_ptr<T[]> buf1 = (child1 != -1)
+ ? std::unique_ptr<T[]>(new T[std::min(nelem_per_maxmsg,nelem)])
+ : nullptr;
 
  auto reduce_impl = [&,this](T* buf, int nelem) {
  MADNESS_ASSERT(nelem <= nelem_per_maxmsg);