<table cellspacing="0" cellpadding="0" border="0" ><tr><td valign="top" style="font: inherit;">Thank you Barry for the replay. Yes I get more or less the same log when I run with the option -log_summary. Please have a look at the attached file.<br><br>Thanks<br><br>Waad<br><br>--- On <b>Thu, 7/31/08, Barry Smith <i><bsmith@mcs.anl.gov></i></b> wrote:<br><blockquote style="border-left: 2px solid rgb(16, 16, 255); margin-left: 5px; padding-left: 5px;">From: Barry Smith <bsmith@mcs.anl.gov><br>Subject: Re: Performance Log Question<br>To: petsc-users@mcs.anl.gov<br>Date: Thursday, July 31, 2008, 9:27 PM<br><br><pre> From the file, it seems you never make an nontrivial PETSc calls. <br>Do you get the same<br>log if you just run with -log_summary?<br><br> Barry<br><br><br><br>Event Count Time (sec) Flops/ <br>sec --- Global --- --- Stage --- Total<br> Max Ratio Max
Ratio Max Ratio Mess Avg <br>len Reduct %T %F %M %L %R %T %F %M %L %R Mflop/s<br>------------------------------------------------------------------------------------------------------------------------<br><br>--- Event Stage 0: Main Stage<br><br>------------------------------------------------------------------------------------------------------------------------<br><br><br><br>On Jul 31, 2008, at 4:33 PM, Waad Subber wrote:<br><br>> Hello,<br>><br>> I am currently solving a 1.2 million by 1.2 million linear system <br>> using PETSc 2.3.3, Patch 13 using domain decomposition (iterative <br>> substructuring using a Krylov Subspace Solver). I'm using a 120 CPU <br>> cluster with InfiniBand interconnect; each node has 8 cores -- 2 <br>> quad-core Xeon CPUs (X5365) at 3.0 GHz, each node having 32 GB of RAM.<br>><br>> After running my code, I generate a log using the following:<br>>
CALL<br>PetscLogPrintSummary(PETSC_COMM_WORLD,"log.txt",ierr)<br>><br>> When looking at the log output, I noticed that the peak and average <br>> number of Flops seems fairly low -- in the case of one run, a peak <br>> of 6.0e7 flops with an average value of 5.2e7. The exact log output <br>> is:<br>><br>> Max Max/Min Avg Total<br>> Time (sec): 5.283e+01 1.02357 5.169e+01<br>> Objects: 2.600e+02 1.00000 2.600e+02<br>> Flops: 3.187e+09 1.69853 2.721e+09 3.265e+11<br>> Flops/sec: 6.165e+07 1.69865 5.264e+07 6.317e+09<br>> Memory: 6.081e+07 1.39801 6.608e+09<br>> MPI Messages: 1.067e+05 1.00000 1.067e+05 1.281e+07<br>> MPI Message Lengths: 5.205e+08 1.00081 4.875e+03 6.245e+10<br>> MPI Reductions: 1.898e+01
1.00000<br>><br>> Is my interpretation correct about this being a fairly low flop <br>> count? Does this mean there's an issue with my code?<br>><br>> I am attaching my log file<br>><br>> Thanks<br>><br>> Waad<br>><br>><br>> <log.txt><br><br></pre></blockquote></td></tr></table><br>