What's the meaning of "Max Mem / Proc" ?

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1

Hi,
I am not very clear to the meaning of "Max Mem / Proc"
in the "GPU Time Info (average)".
Is it the maximal of GPU memory used by one CPU core?

Thanks in advance.

Kai Wang
Institute of Metal Research, CAS

2

If this is in the output for the GPU package,
then Mike can answer it.

Steve

3

Hi, Steve

Yes, it is in the output "GPU Time Info (average)" when using GPU package.

Kai Wang

4

It is the maximum memory used at one time on the GPU for data storage by
a single MPI process. - Mike

5

Hi, Mike

I'm not familiar with parallel computing.
May I do a further confirmation:

Does the "a single MPI process" mean one CPU,
so, if I use 2 nodes, 12 cpu, 1 gpu per nodes,
get 100MB Max Mem / Proc, does it mean
the maximal possible data storage on 1 gpu is
100 MB * 12 = 2400 MB ?
Or it is right if I monopolize these resource?

Thank you in advance.

Kai Wang

6

it is not the maximum memory available it is the maximum memory used.
the mpi processes are the concurrently executing instances of a program
at the o/s process level. often people launch the same number of mpi
procs as cpu cores. for n processes sharing a single gpu, each using x
units of memory space, you don't want n*x > available_gpu_memory.

- Mike