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<TITLE>Performance degradation after upgrade to 3.0.0</TITLE>
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<P><FONT SIZE=2>Hi,<BR>
<BR>
I have also verified that there has been a degradation of performance using the new 3.0 version:<BR>
<BR>
This is my function calling PETSc:<BR>
<BR>
KSP ksp;<BR>
PC pc;<BR>
<BR>
KSPCreate (PETSC_COMM_WORLD, &ksp);<BR>
<BR>
KSPSetOperators (ksp, *A, *A, DIFFERENT_NONZERO_PATTERN);<BR>
<BR>
KSPSetType (ksp, KSPFGMRES);<BR>
<BR>
KSPGetPC (ksp, &pc);<BR>
<BR>
PCSetType (pc, PrecondProc);<BR>
<BR>
KSPSetInitialGuessNonzero (ksp, PETSC_TRUE);<BR>
<BR>
KSPSetTolerances (ksp, 1E-50, maxtol, PETSC_DEFAULT, maxiter);<BR>
<BR>
KSPSetFromOptions (ksp);<BR>
<BR>
KSPSolve (ksp, *b, *x);<BR>
<BR>
KSPGetIterationNumber (ksp, iter);<BR>
<BR>
KSPGetResidualNorm (ksp, res);<BR>
<BR>
KSPDestroy (ksp);<BR>
<BR>
<BR>
with previous version 2.3.3-p6:<BR>
<BR>
Number of iterations: 42 Residual: +7.073781E-13 Time: +8.615024E-03<BR>
<BR>
now:<BR>
<BR>
Number of iterations: 500 Residual: +2.746161E-05 Time: +1.026870E-01<BR>
<BR>
It is reaching maximum number of iterations. The only thing I changed was:<BR>
<BR>
MatSetOption (*A, MAT_SYMMETRIC);<BR>
to<BR>
MatSetOption (*A, MAT_SYMMETRIC, PETSC_TRUE);<BR>
<BR>
I think I didn't change anything else.<BR>
<BR>
<BR>
Regards,<BR>
<BR>
Billy.<BR>
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