mpitune generated rdssm, shm:dapl, and shm-dapl files

[chenwg2000]

I was experimenting with mpitune. When it finishes, I found that quite a few new files are created in directory /opt/intel/impi/4.1.0/intel64/etc

Among these files are:

* mpiexec_rdssm_nn_8_np_128_ppn_16.conf
* mpiexec_shm-dapl_nn_8_np_128_ppn_16.conf
* mpiexec_shm:dapl_nn_8_np_128_ppn_16.conf

When I inspect content of these files:

* shm-dapl contains I_MPI_ADJUST_ALLGATHERV and I_MPI_ADJUST_ALLREDUCE
* shm:dapl contains I_MPI_ADJUST_BCAST I_MPI_ADJUST_GATHER I_MPI_ADJUST_ALLGATHER I_MPI_ADJUST_SCATTER I_MPI_ADJUST_REDUCE
* rdssm contains all the 7 above, and each line of it is the same to either a line in shm-dapl or a line in shm:dapl

AFAIK, rdssm is equivalent to shm:dapl. I'm even more confused when I see both shm-dapl and shm:dapl.

Can any one explain why there are these 3 files? And what the difference is between them?

[James_T_Intel]

Hi,

The reason you see multiple files is because there are multiple ways of specifying the communication fabric/device, and the file names correspond to each method of specifying the fabric/device.

Sincerely,
James Tullos
Technical Consulting Engineer
Intel® Cluster Tools

[chenwg2000]

James Tullos (Intel) wrote:

Hi,

The reason you see multiple files is because there are multiple ways of specifying the communication fabric/device, and the file names correspond to each method of specifying the fabric/device.

Sincerely,
James Tullos
Technical Consulting Engineer
Intel® Cluster Tools

Thank you for your reply. But you answer does not make much sense if the contents of the files are not the same, which I have mentioned in the question. If they had been the same, I won't be confused.

In fact, on my server, the file content of mpiexec_*.conf corresponding to shm-dapl and shm:dapl specifies several IMPI environment variable that are disjoint. But mpiexec_*.conf corresponding to rdssm includes all the IMPI environment variables that are included in mpiexec_*.conf corresponding to shm-dapl and shm:dapl.

Why's that?

[James_T_Intel]

Hi,

Sorry, I misread your post.  I'll investigate what is happening.  You can look through the log from the tuning session to see the reasons why a particular setting was selected for each situation.  If you want to upload that file, I can take a look through it as well.

Sincerely,
James Tullos
Technical Consulting Engineer
Intel® Cluster Tools