I am trying to calculate a function's gradient vector of size 12 on a PC cluster. It seems to be running ok if I request one node with 4 cores by using:
#PBS -l select=1:ncpus=4:mem=1200mb
This way, each processor will calculate 3 elements of the gradient.
Now, I want to use 12 processors to calculate the 12 elements gradient vector in one go, so I tried to request 3 nodes by using:
#PBS -l select=3:ncpus=4:mem=1200mb
>>> rank 7 in job 1 cx1-5-3-2.cx1.hpc.ic.ac.uk_49216 caused collective abort of all ranks exit status of rank 7: return code 29
I am new to MPI. Is there anything I should be aware of when requesting multinodes? Many thanks for reading my thread.