OpenBLAS discussion (was Re: [bug #34822] Mingw panics on a simple complex product)

[Tatsuro MATSUOKA]

Hello

Nitzan and I have been talking about the OpenBLAS at the end part of bug 
tracker id: #34822. (http://savannah.gnu.org/bugs/?34822)

OpenBLAS is a powerful bsd licensed free blas and can be used with Octave.
From this reason, I have post a rely to the maintainers list with cc.

******* Reply to the Nitzan 
I have read https://github.com/xianyi/OpenBLAS/issues/69.

The commitment
https://github.com/xianyi/OpenBLAS/commit/fe613de8e1b72b8225e81556511ac22ea1e2201d

has not been included in the recent tar ball of the source archive.
I will manually modify the code using the above commitment.
Today I do not have enough time. I will report the result tomorrow.
Thank you very much for your investigation and giving me information.
*************

Regards

Tatsuro
--- On Tue, 2012/2/14, Nit Nit wrote:

> 
> Hello Tatsuro,
> 
> I am writing this message directly to you and not to the bug tracker since I 
> think that this response is not related to that bug.
> 
> Regarding your tests with OpenBlas on your i5 cpu, it seems that there was 
> really a problem with auto-detection of Sandy-Bridge (as Nehalem) in the 
> recent master branch but this problem has been just fixed TODAY by the 
> OpenBlas author in the development branch.
> 
> See the discussion in https://github.com/xianyi/OpenBLAS/issues/69.
> 
> I do not have a sandy-bridge cpu so I can't test it but it seems that if you 
> will apply the change in 
> https://github.com/xianyi/OpenBLAS/commit/fe613de8e1b72b8225e81556511ac22ea1e2201d
> (link taken from the discussion thread) and test it on your machine, it will 
> help the author verifying the fix and we may really have a single libblas dll 
> which may be optimized and auto-detects multiple architectures.
> 
> Please note - the issue is labeled as:
> "refs #69. Auto-detect Intel Core i6/i7 (Sandy Bridge) CPU with Nehale…"
> but it deals with sandy-bridge core i5/i7 (probably i6 is a tipo mistake) 
> which include your i5-2400 machine.
> 
> Regards
> Nitzan
> 
> On Mon, Feb 13, 2012 at 11:57 AM, Tatsuro MATSUOKA <address@hidden> wrote:
> Follow-up Comment #21, bug #34822 (project octave):
> 
> I have rebuild the OpenBLAS
> 
> 
> 
> make CC=i686-pc-mingw32-gcc FC=i686-pc-mingw32-gfortran DYNAMIC_ARCH=1
> TARGET=NEHALEM NUM_THREADS=4
> 
> 
> The build reports are
> 
>  OpenBLAS build complete.
> 
>   OS               ... WINNT
>   Architecture     ... x86
>   BINARY           ... 32bit
>   C compiler       ... GCC  (command line : i686-pc-mingw32-gcc)
>   Fortran compiler ... GFORTRAN  (command line : i686-pc-mingw32-gfortran)
>   Library Name     ... libopenblasp-r0.1alpha2.4.lib (Multi threaded; Max
> num-threads is 4)
> 
> 
> 
> 
> octave:1>  n=2000; A=randn(n); B=randn(n);tic; C=A*B; t=toc,
> MFLOPS=2*n^3/t*1e-6
> t =  0.96606
> MFLOPS = 1.6562e+004
> t =  1.0561
> MFLOPS = 1.5151e+004
> t =  0.97106
> MFLOPS = 1.6477e+004
> t =  1.1741
> MFLOPS = 1.3628e+004
> t =  0.95905
> MFLOPS = 1.6683e+004
> 
> 
> 
> The results were the mostly equaled to that were executed previously.
> 
> For my case, auto detection seems not to be effective.
> 
> 
> 
>     _______________________________________________________
> 
> Reply to this item at:
> 
>   <http://savannah.gnu.org/bugs/?34822>
> 
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> 
> 
>