Subject: bug#49096: closed (Re: bug#49096: [PATCH] gnu: petsc: Link against OpenBLAS rather than LAPACK.)

From: [email-masked] (GNU bug Tracking System)
Date: Tue, 22 Jun 2021 15:58:02 +0000

Your bug report

#49096: [PATCH] gnu: petsc: Link against OpenBLAS rather than LAPACK.

which was filed against the guix-patches package, has been closed.

The explanation is attached below, along with your original report.
If you require more details, please reply to [email-masked].

-- 
49096: http://debbugs.gnu.org/cgi/bugreport.cgi?bug=49096
GNU Bug Tracking System
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Subject: Re: bug#49096: [PATCH] gnu: petsc: Link against OpenBLAS rather than LAPACK.
From: Ludovic Courtès <[email-masked]>
To: Efraim Flashner <[email-masked]>
Cc: Florent Pruvost <[email-masked]>, Emmanuel Agullo <[email-masked]>, [email-masked]
Date: Tue, 22 Jun 2021 17:57:06 +0200
List-Id: <debbugs-submit.debbugs.gnu.org>

Efraim Flashner <[email-masked]> skribis:

> On Fri, Jun 18, 2021 at 06:12:04PM +0200, Ludovic Courtès wrote:
>> From: Ludovic Courtès <[email-masked]>
>> 
>> OpenBLAS performs better than LAPACK, the reference implementation.
>> This is also consistent with the choice of BLAS/LAPACK implementations
>> made in most other packages.
>> 
>> * gnu/packages/maths.scm (petsc)[inputs]: Replace LAPACK by OPENBLAS.
>> [arguments]: Pass "--with-openmp=1".

[...]

> It sounds reasonable to me.

Pushed as c7a5c3e0bba2ac3d197b219d21527863308b75dd.

Ludo'.

Subject: [PATCH] gnu: petsc: Link against OpenBLAS rather than LAPACK.
From: Ludovic Courtès <[email-masked]>
To: [email-masked]
Cc: Ludovic Courtès <[email-masked]>
Date: Fri, 18 Jun 2021 18:12:04 +0200
List-Id: <debbugs-submit.debbugs.gnu.org>

From: Ludovic Courtès <[email-masked]>

OpenBLAS performs better than LAPACK, the reference implementation.
This is also consistent with the choice of BLAS/LAPACK implementations
made in most other packages.

* gnu/packages/maths.scm (petsc)[inputs]: Replace LAPACK by OPENBLAS.
[arguments]: Pass "--with-openmp=1".
---
 gnu/packages/maths.scm | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

Hi!

Usually there’s no reason to depend on the reference (“Netlib”) BLAS/LAPACK
implementations because they perform poorly.  This change is one way to
bring consistency here.

Thoughts?

Ludo’.

diff --git a/gnu/packages/maths.scm b/gnu/packages/maths.scm
index a79d546abd..8d47f91310 100644
--- a/gnu/packages/maths.scm
+++ b/gnu/packages/maths.scm
@@ -2417,7 +2417,7 @@ September 2004}")
      `(("python" ,python-2)))
     (inputs
      `(("gfortran" ,gfortran)
-       ("lapack" ,lapack)
+       ("openblas" ,openblas)
        ("superlu" ,superlu)
        ;; leaving out hdf5 and fftw, as petsc expects them to be built with mpi
        ;; leaving out opengl, as configuration seems to only be for mac
@@ -2428,6 +2428,7 @@ September 2004}")
        #:configure-flags
        `("--with-mpi=0"
          "--with-openmp=1"
+         "--with-openblas=1"
          "--with-superlu=1")
        #:make-flags
        ;; Honor (parallel-job-count) for build.  Do not use --with-make-np,
-- 
2.32.0