topic IMSL with Parallelization in Intel® Fortran Compiler

IMSL with Parallelization

eleteroboltz — Tue, 06 Sep 2011 03:53:41 GMT

I'm usingIntel Visual Fortran 11.1 x64 andIMSL x64 v7.0 withMicrosoft Visual Studio 2008.

I'm using the routine IVPAG from IMSL and I noticed that it is using automatically parallelism to solve the problem, since I see in task manager my 4 core processor running all at 100%.

I'm doing some benchmark code and I would like the IMSL to notuse CPU parallelization.

How do I disable parallel computing in my case???

Thanks in advance.

IMSL with Parallelization

Steven_L_Intel1 — Tue, 06 Sep 2011 13:43:11 GMT

You will have to ask Rogue Wave about whether it is possible to turn off threading in IMSL 7. Intel does not provide support for that version of IMSL.

IMSL with Parallelization

TimP — Tue, 06 Sep 2011 14:01:53 GMT

Did you look into OMP_NUM_THREADS, or, if it is using MKL, at the corresponding MKL options, including linking mkl_sequential?

IMSL with Parallelization

jimdempseyatthecove — Tue, 06 Sep 2011 16:39:43 GMT

Try placing a keyboard input routine ("Press any key to continue") into the front of the program (console input or message box).
Run, then when at prompt, launch task manager, locate your process (should be program name)
right click and do Properties. You should find check boxes for Affinity. Unselect all but one of the check boxes. Close Task Manager and click into your app window and press Enter.
You can also use WIN32 API to set Affinity restrictions. This has to be done before IMSL launches additional threads.

Jim Dempsey

IMSL with Parallelization

eleteroboltz — Fri, 09 Sep 2011 03:05:17 GMT

Thank you.

I turned off the parallelization by adding the command:

KMP_AFFINITY=proclist=[0],explicit

at Project>Properties>Debuggind>Enviroment

This way the code only use the processor 0.

To parallelize (4 cores processor) again it is necessary to change the comand to:

KMP_AFFINITY=proclist=[0,1,2,3],explicit