running two users/m-files in parallel on Xeon Phi coproccessor

I'm running MATLAB 2015a with 2 Xeon Phi coproccessor on a Win 2012 server. If I run a single m-file there is a boost in performance. However, when I try to run 2 m-flies or by 2 users in parallel the running time decreases significantly (by order of magnitude) for both cases.

Is it indeed normal and there is no way to allow several users to use Xeon Phi in parallel? or is there a way to resolve this issue?

[Anatoli Juditsky]

Hello, I am desperately looking for help when trying to make work automatic offload with matlab 2016a. I have succeeded to make it work with R and linpack examples. Yet, cannot get it work with matlab which does seem ignore the Phi. I am using windows 10 pro. Is there a magic startup option to be modified? I am really at loss... Regards,

Answer 1

[Jan]

It depends on the tasks. If both programs call multi-threaded functions and the Matlab routines try to start as many threads as the number of cores, the preformance can degrade. If the programs access the hard disk a slow down is expected also. So please post more specifically what the bottlenecks are. The profiler might help you to identify them.

[Arik Yochelis]

Thank you! The solution is indeed in this direction and can be resolved using OFFLOAD_DEVICE options