Hi Hong, Thanks for your reply. I check the attachment sent last time and I miss some very information. I attached the complete info with this email. Sorry for this.
I also tried other matrix ordering like mat_mumps_icntl_7 2 and I got the similar performance. I checked the configuration log file on that cluster, they use --download-f-blas-lapack=1 instead of using optimal BLAS. Would this be the problem which cause the poor performance? Actually the mumps runs quite slow, at14 Gflop/s, which is far from the machine's peak. Thanks. Wen > > Wen : > > > Reply to > > > >> This is weird. Try > >> 1) increase work space with > >> -mat_mumps_icntl_14 50 (default is 20) > >> 2) different matrix orderings with > >> -mat_mumps_icntl_7 2 (or number from 0 to 6) > >> > >> Run your code with '-log_summary' and see which routine causes this huge > >> difference. > >> > > Why your '-log_summary' only gives > KSPSolve 4 1.0 2.2645e+03 1.0 0.00e+00 0.0 3.9e+04 3.6e+02 > 5.4e+01 96 0 27 0 9 96 0 27 0 9 0 > PCSetUp 4 1.0 2.2633e+03 1.0 0.00e+00 0.0 0.0e+00 0.0e+00 > 3.4e+01 96 0 0 0 6 96 0 0 0 6 0 > PCApply 4 1.0 1.1641e+00 1.0 0.00e+00 0.0 3.9e+04 3.6e+02 > 2.0e+01 0 0 27 0 3 0 0 27 0 3 0 > > I get > petsc-dev/src/ksp/ksp/examples/tutorials>mpiexec -n 2 ./ex2 -pc_type lu > -pc_factor_mat_solver_package mumps -log_summary > MatMult 2 1.0 1.6904e-04 1.0 4.44e+02 1.0 4.0e+00 5.6e+01 > 0.0e+00 0 47 25 13 0 0 47 33 13 0 5 > MatSolve 2 1.0 3.8259e-03 1.0 0.00e+00 0.0 8.0e+00 1.9e+02 > 6.0e+00 10 0 50 84 7 11 0 67 87 9 0 > MatLUFactorSym 1 1.0 2.9058e-03 1.0 0.00e+00 0.0 0.0e+00 0.0e+00 > 8.0e+00 7 0 0 0 9 8 0 0 0 11 0 > MatLUFactorNum 1 1.0 2.0120e-03 1.0 0.00e+00 0.0 0.0e+00 0.0e+00 > 2.0e+00 5 0 0 0 2 6 0 0 0 3 0 > ... > > I like to check these functions. In addition, have you tried other matrix > orderings? > Hong > > > > >> Hong > >> > >> > > I just tested the problem according to what you suggested. I set icntl_14 > > = 50 and icntl_7 = 5 (METIS). The problem still persisted. The first > solve > > took 920 second and second solve took 215 second with same nonzero > pattern > > pc set up. I also attached the log_summary output file. Do you have any > > further suggestion? Thanks. > > > > Regards, > > Wen > > > > > > -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.mcs.anl.gov/pipermail/petsc-users/attachments/20120430/a7d3d921/attachment.htm> -------------- next part -------------- A non-text attachment was scrubbed... Name: petsc_summary_info Type: application/octet-stream Size: 18496 bytes Desc: not available URL: <http://lists.mcs.anl.gov/pipermail/petsc-users/attachments/20120430/a7d3d921/attachment.obj>
