message: add sleep to reader to serialize printout
diff: @@ -169,8 +169,8 @@ void SerialPrintout(std::vector<VarInfo> &varinfos, int rank, int nproc)
  #ifdef ADIOS2_HAVE_MPI
  if (rank < nproc - 1)
  {
  - // std::chrono::milliseconds timespan(100);
  - // std::this_thread::sleep_for(timespan);
  + std::chrono::milliseconds timespan(100);
  + std::this_thread::sleep_for(timespan);
  MPI_Send(&token, 1, MPI_INT, rank + 1, 0, readerComm);
  }
  #endif
  