#include <unistd.h> #include <stdio.h>
int main()
{
char name[100]; gethostname(name, sizeof(name)); printf("%s says Hello!\n", name); return 0;
}
The following is the command line used to compile this program:$ cc hw_hostname.c
NOTE: The following invocations of the sample hw_hostname program are run on a SLURM
When run on the login node, it shows the name of the login node, n16 in this case:
$ ./hw_hostname n16 says Hello!
When you use the srun command to submit this program, it runs on one of the compute nodes. In this instance, it runs on node n13:
$ srun ./hw_hostname n13 says Hello!
Submitting the same program again with the srun command may run this program on another node, as shown here:
$ srun ./hw_hostname n12 says Hello!
The srun can also be used to replicate the program on several cores. Although it is not generally useful, it illustrates the point. Here, the same program is run on 4 cores on 2 nodes.
$ srun
n13 says Hello!
n14 says Hello!
n14 says Hello!
The output for this command could also have been 1 core on each of 4 compute nodes in the SLURM allocation.
5.3 Submitting a Parallel Job
When submitting a parallel job, you can specify the use of
•“Submitting a Parallel Job That Uses the
5.3.1Submitting a Non-MPI Parallel Job
to submit a parallel jobUse the following format of the LSF bsub command to submit a parallel job that does not make use of
bsub
5.3 Submitting a Parallel Job | 51 |