Accuracy of profiling
Mahmood N <[email protected]>
| Newsgroups | gmane.linux.oprofile |
|---|---|
| Message-ID | <[email protected]> |
Hi,I have a concern over the accuracy of profiling. I profiled two executions immediately. The second execution took less time than the first one. That is correct in real world because of caching. However, I don't expect to see such an effect in profiling. Events were actively counted for 37.9 seconds. Event counts (actual) for /home/mahmood/spec-cpu2006-x86_64/benchspec/CPU2006/401.bzip2/exe/bzip2_base.amd64-m64-gcc44-nn: Event Count % time counted CPU_CLK_UNHALTED 109,637,705,266 100.00 RETIRED_INSTRUCTIONS 108,789,176,110 100.00 Events were actively counted for 35.9 seconds. Event counts (actual) for /home/mahmood/spec-cpu2006-x86_64/benchspec/CPU2006/401.bzip2/exe/bzip2_base.amd64-m64-gcc44-nn: Event Count % time counted CPU_CLK_UNHALTED 107,924,858,901 100.00 RETIRED_INSTRUCTIONS 108,708,808,686 100.00 Another thing is that I expect the same number of RETIRED_INSTRUCTIONS since bzip2 has a number of fixed static instructions (input file in the same in both runs) and doesn't matter how many times it is executed. Regards, Mahmood ------------------------------------------------------------------------------ _______________________________________________ oprofile-list mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/oprofile-list