I have a customer who has an application that when run under pfmon reports 154 billion CPU_CYCLES used (appears to be a reasonable value). When this same application is run under Hpcrun (from HPCToolkit using PAPI) it only reports about 2 billion CPU_CYCLES used. These tests are run on an Intel IA64 platform.
This application runs as a single thread and does not set a signal handler or mask the SIGIO signal. Hpcrun produces 8 data output files when run on this application. One for the application itself, 4 for bash scripts the application runs, 2 for 'rm' commands the application executes and 1 for a gzip command it runs. The customer wants to know why Hpcrun only reports a little over 1% of the cpu cycles used. I have been trying to compare what pfmon does to what hpcrun does and it seems that the only debug data available for both runs is the kernel debug data written by perfmon. This data clearly shows that Hpcrun/Papi is using the perfmon services differently than pfmon does. I tried to attach the debug output for these two runs to this mail but that exceeded the allowed message size for the list. I tried adding code (as a test case) to the Papi signal handler to count and print the number of signals paid during the run. The values printed seemed to pretty much match the values reported as number of samples when hpcprof is run on the hpcrun data files. This was an attempt to detect if my problem was handling signals or getting them and I think this test showed the problem is in getting them. I have also browsed this mailing list and found a thread called "papi on compute node linux" which was last updated 2008-03-10. The discussion in this thread sounds to me like it could easily explain what I am seeing. Is there a way I can determine if this discussion (ie: loosing interrupts) is what I am seeing ? Thanks for any help you can provide. Gary ------------------------------------------------------------------------- This SF.net email is sponsored by the 2008 JavaOne(SM) Conference Don't miss this year's exciting event. There's still time to save $100. Use priority code J8TL2D2. http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone _______________________________________________ perfmon2-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/perfmon2-devel
