RE: Can't use 256 nodes for symmetric computing

2016-01-27T22:46:34Z

Hi David,

For timely answers to technical questions like this, you should submit a ticket to help@xsede.org. But, I should be able to help you here.

With the upgrade to Intel 15 and Intel MPI 5, the behavior of mpiexec.hydra (which starts the mpi job) changed. There is an internal buffer that processes the arguments for each executable, and the handling of this buffer has changed. This error doesn't occur when using Intel MPI 4.

To work around this buffer overflow, I've created a version of ibrun.symm that does not set up the MIC environment using the mpiexec.hydra task starter. This reduces the number of characters for each excutable command and avoids the buffer overflow issue.

However, using this version of ibrun.symm starts the MIC executable with the incorrect environment. So, a wrapper script must be used also. I've attached the modified version of ibrun.symm and the wrapper script to this response.

To use this version of ibrun.symm, replace your current run line with the following:

./ibrun.symm.no_env -m "./mic_env_run ./arc_mpi.exe.mic" -c "./arc_mpi.exe"

If you continue to have problems with this, please submit a ticket.

Thanks,

John

RE: ibrun fails

2013-06-25T17:25:02Z

Hi Mikhail,

If you added your keys to ~/.ssh/authorized_keys without removing the existing keys, it should be fine.

You can also put your personal keys in ~/.ssh/authorized_keys2.

Thanks,

John