On Apr 4, 2007, at 11:12 AM, po...@cc.gatech.edu wrote:

I want to see how profiling is done .I need to track open mpi _send command. And so need to see how profiling is done.I dont know how to use PMPI_SEND.
Can anybody help me???

Generally, you just write an MPI_Send function yourself, like this:

my_send.c:

include "mpi.h"
int MPI_Send(void *buf, int count, MPI_Datatype type, int dest,
             int tag, MPI_Comm comm) {
  int ret;
  /* ...gather whatever statistics you want ... */
  ret = PMPI_Send(buf, count, type, dest, tag, comm);
  /* ...gather whatever statistics you want ... */
  return ret;
}

Then compile my_send.c into your application (either as a standalone library or as part of the application itself). It'll naturally intercept all calls to MPI_Send (as long as it is the rightmost linker unit before -lmpi on the command line -- so, when using the wrapper compilers, the last linker unit on the right, since "-lmpi" is added automatically by the wrapper compilers), do your stats gathering, invoke the back-end PMPI function, etc.

See chapter 8 of the MPI-1 standard for more information:

    http://www.mpi-forum.org/docs/mpi-11-html/node152.html#Node152

--
Jeff Squyres
Cisco Systems

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