topic mkl ILAENV question in Intel® oneAPI Math Kernel Library

mkl ILAENV question

Abo__Gavin — Thu, 25 Oct 2012 10:50:33 GMT

I'm using Update 11 of composerxe 2011, but the following may occur in earlier and later verisons as well. When I run the attached test case (tilaenv.f) for intel64, ILAENV returns 128. However, when I run the following case for ia32, ILAENV returns 640. Is 640 the correct return value? It just seems large compared to the return value for intel64, so I'm wondering if iILAENV should be returning 64. If so, how can I fix it? I would appreciate any feedback.

I obtain 64 as the return

mecej4 — Thu, 25 Oct 2012 11:53:59 GMT

I obtain 64 as the return value with MKL 10.3.11 Product Build 20120606 (IA32) and compiler 12.1.5.344 Build 2012-0612 .

With the Intel64 13.0 update

TimP — Thu, 25 Oct 2012 13:35:11 GMT

With the Intel64 13.0 update 1 or 12.1 update 13 packages for Windows, I get 640 from MKL ilaenv. With netlib ilaenv, I get 64, so it seems MKL doesn't work the same as lapack 3.2.1 reference source. The source code appears to date from over 30 years ago.

the same with me - ia32

Gennady_F_Intel — Thu, 25 Oct 2012 14:18:59 GMT

the same with me - ia32 version returned - 64, but intel64 - 640. windows, MKL v.11.0 we will check what' going with this code.

Ok and thanks. By the way, I

Abo__Gavin — Thu, 25 Oct 2012 14:35:18 GMT

Ok and thanks. By the way, I'm using the linux package.

After thinking a bit more

mecej4 — Thu, 25 Oct 2012 15:21:07 GMT

After thinking a bit more about this issue, I begin to ask why the returned value, being a tuning parameter (= optimum block size), should be the same between the MKL and ref. Lapack implementations. If the MKL optimum value is related to optimized assembler code, there is nothing wrong with such a discrepancy. Furthermore, there is nothing wrong with the value being different for different machine architectures (IA32 and X64).

Hello,

Gennady_F_Intel — Mon, 04 Feb 2013 06:27:03 GMT

Hello,

This issue has been fixed in MKL v.11.0 update 2 released yesterday.

You can download this update from intel registration center and check the problem on your side.

--Gennady