How can I get mpiprofile information from a parfor script?

I have been unable to launch the parallel profiler outside of an spmd block, which prevents usage of parfor. I always get the same error when I try to turn on the profiler, both with and without a parallel pool running. Is there something obvious that I am missing, or is there something more nuanced about how mpiprofile is used?

>> mpiprofile on

Error using mpiprofile (line 162)

MPIPROFILE on must run in pmode or as part of a parallel job.

See doc for MPIPROFILE in the Parallel Computing Toolbox.

Answer 1

[Raymond Norris]

Hi John,

Prior to R2020a, you need to call mpiprofile within pmode or a parallel job, as shown in this example:

https://www.mathworks.com/help/releases/R2019b/parallel-computing/mpiprofile.html

In R2020a, we began sunsetting pmode. With that we also allow for mpiprofile to be called either inside or outside of an spmd block, such as with this contrived example

p = parpool('local',4);
Starting parallel pool (parpool) using the 'local' profile ...
Connected to the parallel pool (number of workers: 4).

mpiprofile on
 
A = distributed.rand(400);
b = distributed.rand(400,1);
x = A\b;

mpiprofile off
mpiprofile viewer

Raymond

[John B.]

Hi Raymond,

That worked for me. Thanks!

-John