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<p class="MsoNormal">Hi everybody!<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I kept experimenting with slepc and GPUs, and when I turned to SVD I found out that the hands-on exercise on SVD [#4] doesn’t run properly.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">If I run it on CPU it works fine, whereas…<o:p></o:p></p>
<p class="MsoNormal">$ mpirun -np 1 slepcSVD -file $SLEPC_DIR/share/slepc/datafiles/matrices/rdb200.petsc -bv_type vecs -mat_type aijcusp -on_error_abort<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Singular value problem stored in file.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Reading REAL matrix from a binary file...<o:p></o:p></p>
<p class="MsoNormal">[0]PETSC ERROR: BVScaleColumn() line 380 in /gpfs/rrcfd/rruk-students/apps/slepc/src/sys/classes/bv/interface/bvops.c Scalar value must be same on all processes, argument # 3<o:p></o:p></p>
<p class="MsoNormal">[0]PETSC ERROR: ------------------------------------------------------------------------<o:p></o:p></p>
<p class="MsoNormal">[0]PETSC ERROR: Caught signal number 11 SEGV: Segmentation Violation, probably memory access out of range<o:p></o:p></p>
<p class="MsoNormal">[0]PETSC ERROR: Try option -start_in_debugger or -on_error_attach_debugger<o:p></o:p></p>
<p class="MsoNormal">[0]PETSC ERROR: or see http://www.mcs.anl.gov/petsc/documentation/faq.html#valgrind<o:p></o:p></p>
<p class="MsoNormal">[0]PETSC ERROR: or try http://valgrind.org on GNU/linux and Apple Mac OS X to find memory corruption errors<o:p></o:p></p>
<p class="MsoNormal">[0]PETSC ERROR: likely location of problem given in stack below<o:p></o:p></p>
<p class="MsoNormal">[0]PETSC ERROR: --------------------- Stack Frames ------------------------------------<o:p></o:p></p>
<p class="MsoNormal">[0]PETSC ERROR: Note: The EXACT line numbers in the stack are not available,<o:p></o:p></p>
<p class="MsoNormal">[0]PETSC ERROR: INSTEAD the line number of the start of the function<o:p></o:p></p>
<p class="MsoNormal">[0]PETSC ERROR: is given.<o:p></o:p></p>
<p class="MsoNormal">[0]PETSC ERROR: [0] PetscAbortErrorHandler line 56 /gpfs/rrcfd/rruk-students/apps/petsc/src/sys/error/errabort.c<o:p></o:p></p>
<p class="MsoNormal">[0]PETSC ERROR: [0] PetscError line 363 /gpfs/rrcfd/rruk-students/apps/petsc/src/sys/error/err.c<o:p></o:p></p>
<p class="MsoNormal">[0]PETSC ERROR: [0] BVScaleColumn line 377 /gpfs/rrcfd/rruk-students/apps/slepc/src/sys/classes/bv/interface/bvops.c<o:p></o:p></p>
<p class="MsoNormal">[0]PETSC ERROR: [0] EPSFullLanczos line 357 /gpfs/rrcfd/rruk-students/apps/slepc/src/eps/impls/krylov/epskrylov.c<o:p></o:p></p>
<p class="MsoNormal">[0]PETSC ERROR: [0] EPSSolve_KrylovSchur_Symm line 41 /gpfs/rrcfd/rruk-students/apps/slepc/src/eps/impls/krylov/krylovschur/ks-symm.c<o:p></o:p></p>
<p class="MsoNormal">[0]PETSC ERROR: [0] EPSSolve line 83 /gpfs/rrcfd/rruk-students/apps/slepc/src/eps/interface/epssolve.c<o:p></o:p></p>
<p class="MsoNormal">[0]PETSC ERROR: [0] SVDSolve_Cross line 155 /gpfs/rrcfd/rruk-students/apps/slepc/src/svd/impls/cross/cross.c<o:p></o:p></p>
<p class="MsoNormal">[0]PETSC ERROR: [0] SVDSolve line 92 /gpfs/rrcfd/rruk-students/apps/slepc/src/svd/interface/svdsolve.c<o:p></o:p></p>
<p class="MsoNormal">[0]PETSC ERROR: User provided function() line 0 in unknown file (null)<o:p></o:p></p>
<p class="MsoNormal">--------------------------------------------------------------------------<o:p></o:p></p>
<p class="MsoNormal">mpirun noticed that process rank 0 with PID 11264 on node gpu3 exited on signal 11 (Segmentation fault).<o:p></o:p></p>
<p class="MsoNormal">--------------------------------------------------------------------------<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I am using the same command line options that work just fine on hands-on exercises 1 and 2, which feature EPS solvers.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Any hint appreciated.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Best regards,<o:p></o:p></p>
<p class="MsoNormal">Massimiliano Leoni<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
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