On Fri, May 3, 2013 at 10:20 PM, Jed Brown <jedbrown at mcs.anl.gov> wrote:
> Dharmendar Reddy <dharmareddy84 at gmail.com> writes: > > > Hello, > > I see an interesting behavior when i call EPSSolve in a loop. > Can > > you help me figure out whats going on ? > > > > I have a setup like this to solve a A x = lambda B x (Generalized > > Hermitian problem) > > > > type eigenSolver_t > > EPS :: eps > > > > end type eigenSolver_t > > > > the type has bound procedure which calls EPSSetOperators and EPSSolve > when > > eigenSolver%solve() is called > > > > Now i run a for loop > > > > do ic=1,111 > > call eigenSolver(ic)%solve() > > end do > > > > I print the time for each solve. The operators A,B =A1,B1 for ic=1 to 50 > > A2,B2 for ic=51 to 80 and A3,B3 for ic=81 to 111 > > > > Now i see that time per solve per ic is almost constant when i use > > -eps_type lapack. > > How do you figure? It looks like it increases by more than an order of > magnitude. > > You are right, The time per solve increases in both case, see the attached plot. I have attached the stage wise log_summary . > Always send -log_summary output when asking about performance. In this > case, it would be nice to use a different stage to log each solve. > > > But for, defualt solver, time per solve seem to increase with increasing > > ic. Have look at the attached timing information. > > > > Also, Time per solve using lapack is lower than any of the iterative > > solvers i have tried. Problem size is about 100 x 100, operators are > > tri-diagonal. > > I'm not surprised. That problem is tiny. > -- ----------------------------------------------------- Dharmendar Reddy Palle Graduate Student Microelectronics Research center, University of Texas at Austin, 10100 Burnet Road, Bldg. 160 MER 2.608F, TX 78758-4445 e-mail: dharmareddy84 at gmail.com Phone: +1-512-350-9082 United States of America. Homepage: https://webspace.utexas.edu/~dpr342 -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.mcs.anl.gov/pipermail/petsc-users/attachments/20130504/34587ef1/attachment-0001.html> -------------- next part -------------- A non-text attachment was scrubbed... Name: TimePerSolveEPS.tif Type: image/tiff Size: 51654 bytes Desc: not available URL: <http://lists.mcs.anl.gov/pipermail/petsc-users/attachments/20130504/34587ef1/attachment-0001.tif> -------------- next part -------------- A non-text attachment was scrubbed... Name: solvetimeDefault Type: application/octet-stream Size: 436043 bytes Desc: not available URL: <http://lists.mcs.anl.gov/pipermail/petsc-users/attachments/20130504/34587ef1/attachment-0002.obj> -------------- next part -------------- A non-text attachment was scrubbed... Name: solvetimeLapack Type: application/octet-stream Size: 225133 bytes Desc: not available URL: <http://lists.mcs.anl.gov/pipermail/petsc-users/attachments/20130504/34587ef1/attachment-0003.obj>
