Stress testing of Intel OpenMP library - More than 18,600 OpenMP threads created in a parallel region

[SergeyKostrov]

Hi everybody,

I'd like to share results of stress testing ofIntel OpenMP library for a 32-bit platform:

libiomp5md.dll

Intel OMP Performance Library
version 5.0.20111219 for IA-32 architecture
built on 2011-12-19 17:12:07 UTC

A purpose of the stress test was as follows:

Create as many as possible OpenMP threads in a parallel region on aone CPU system.

Details:

It isstated by Intel that up to 16,384 OpenMP threads could be created in a parallel region. This is not true,
because a simpletest application easily created more than 18,600 OpenMP threads on a 32-bit Windows XP
operating system ( 4GB of Virtual Memory ).

How would I compare Intel OpenMP library with Microsoft OpenMP library?

Intel's library is far more advancedand demonstrated outstanding capabilities (!).Microsoft's library
doesn't allow to create more than 64 OpenMP threads in a parallel region. Intel's OpenMP library could be used
forsophisticated scientific projects that require a veryhigh level of parallelization.

Fourscreenshootswill beenclosed.

Best regards,
Sergey

[SergeyKostrov]

Related posts for review:

http://software.intel.com/en-us/forums/showthread.php?t=105009&o=a&s=lr
http://software.intel.com/en-us/forums/showthread.php?t=103375&o=a&s=lr
http://software.intel.com/en-us/forums/showthread.php?t=104247&o=a&s=lr

[SergeyKostrov]

[SergeyKostrov]

[SergeyKostrov]

I found a very interesting article regarding limits of Windows platform(s):

http://blogs.technet.com/b/markrussinovich/archive/2009/07/08/3261309.aspx

[SergeyKostrov]

I've done some review and unfortunately a Post #4 is a spam-post. It is not related to the subject of the thread.

Best regards,
Sergey

[SergeyKostrov]

Quoting billywesley

I am little bit comfused in terms of How it actually works? Can you explain it in brief?

I've created a smalltest-case in C++ that uses some OpenMP functionalityand compiled it with Intel C++ compiler.
I could post the source codes if you need and please confirm me.

Best regards,
Sergey

[sureshgupta22]

It means that theunion 'my_union_t' can not be splitted in two cache lines. Sorry for a little deviation from the main subject.

[SergeyKostrov]

Quoting sureshgupta22

It means that theunion 'my_union_t' can not be splitted in two cache lines. Sorry for a little deviation from the main subject.

Sorry, but it looks like that statementshould beaddressedto a different thread.

[sureshgupta22]

It is not related to the subject of the thread.

[Bernard]

>>>I found a very interesting article regarding limits of Windows platform(s):>>> Thanks very insightful information.