On Fri, Mar 24, 2017 at 8:43 AM, Eloisa Bentivegna <eloisa.bentivegna@ct.infn.it> wrote:

Hi all,

still on the KNL topic, I realize there was a question I ignored, and
which perhaps is worth pursuing.

On 01/03/17 21:43, Ian Hinder wrote:
> Eloisa: does Carpet report the vector size of the KNL as 8? From the
> wikipedia entry, I would expect that to be the case, but I think you
> mentioned to me that it was reporting 4.

That's correct. In my output I find:

===============================================================
INFO (Vectors): Using vector size 4 for architecture AVX (64-bit precision)
===============================================================

Is this not supposed to be so? And in this case, is there anything I can
do about it?

You should see a vector size of 8, and a message containing "AVX512 (64-bit precision)". If you do not do this, then there is a problem with the compiler options -- this decision is made at compile time. You might need to specify "-march=knl" to GCC, or a similar option to the Intel compiler, or you could build on a KNL node and use "-march=native" or "-xHost".

-erik

> Eloisa, are you using LoopControl?

Yes.

Eloisa
_______________________________________________
Users mailing list
Users@einsteintoolkit.org
http://lists.einsteintoolkit.org/mailman/listinfo/users

Erik Schnetter <schnetter@cct.lsu.edu>
http://www.perimeterinstitute.ca/personal/eschnetter/