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<p>I am micromagnetic (MAGPAR) software developer. Old Magpar
version has been using petsc 3.1-p8. I have decided to upgrade to
petsc 3.19.2 with avx512 support. <span class="Y2IQFc" lang="en">Unfortunately
there appeared an error during software testing. Error appeares
in ranning code after proper compiling and linking. The bug is
in a code part which initializes matrix in petsc library
versions: 3.19.2, 3.19.1, 3.19.0 and also from 3.18.5 to 3.18.0.
If we use petsc version 3.17.5 the error doesn't appear. With
this version (3.17.5) all is ok and simulation is running
without any errors or throwing exceptions. My guess is linked to
avx512 implementation which is good up to 3.17.5 version and
buggy in upper mentioned versions with higher numbers. Avx512 is
buggy according to tested SeqAij matrices.</span></p>
<p><span class="Y2IQFc" lang="en">The exception is not thrown if we
comment code fragment below.<br>
</span></p>
<p><span class="Y2IQFc" lang="en">ierr = MatCreateSeqAIJ(<br>
PETSC_COMM_SELF,<br>
nvert,nvert,<br>
0,ia,<br>
&mat<br>
);CHKERRQ(ierr);<br>
ierr = MatSetFromOptions(mat);CHKERRQ(ierr);</span></p>
<p><span class="Y2IQFc" lang="en">ia - is number of nonzeros array
which is obtained according parmetis partitioning. There were
the same version of parmetis (3.1.1) in the all considered
cases.<br>
</span></p>
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