On Thu, Feb 23, 2012 at 10:16 PM, Ramachandra CN <cn.ramachan...@gmail.com> wrote: > Hello, > > I have some questions related to hardware prefetcher events on Intel Xeon > processor with the below configuration. > $ uname -a > Linux 2.6.34-gentoo-r1 #2 SMP Mon Feb 20 12:07:35 CST 2012 x86_64 Intel(R) > Xeon(R) CPU E5520 @ 2.27GHz GenuineIntel GNU/Linux > > I am trying to count the number of hardware prefetch events, before and > after disabling hardware prefetching using BIOS. > I have followed the steps mentioned in the below link to disable h/w > prefetching in BIOS. > http://software.intel.com/en-us/articles/optimizing-application-performance-on-intel-coret-microarchitecture-using-hardware-implemented-prefetchers/ > Something is not right here. You processor E5520 is not a Core micro-architecture but Nehalem-EP. As such, I believe the technique above to disable HW prefetcher does not apply.
> However I don't see much difference in the values of the counter after h/w > prefetching is disabled. The counter value remains approximately the same > before and after disabling h/w prefetching. I also tried > using "PERF_COUNT_HW_CACHE_L1D:PREFETCH" event. But don't see much > difference. > I have used the perf_examples program of libpfm-4.2,.0 as below. > ./task -e L1D_PREFETCH:REQUESTS openmp_test > > Could someone in the group please comment if expecting these counters to > change, after disabling h/w prefetching in BIOS is correct? > > Regards, > Ram > Graduate student > > University of Houston > > > > ------------------------------------------------------------------------------ > Virtualization & Cloud Management Using Capacity Planning > Cloud computing makes use of virtualization - but cloud computing > also focuses on allowing computing to be delivered as a service. > http://www.accelacomm.com/jaw/sfnl/114/51521223/ > _______________________________________________ > perfmon2-devel mailing list > perfmon2-devel@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/perfmon2-devel > ------------------------------------------------------------------------------ Virtualization & Cloud Management Using Capacity Planning Cloud computing makes use of virtualization - but cloud computing also focuses on allowing computing to be delivered as a service. http://www.accelacomm.com/jaw/sfnl/114/51521223/ _______________________________________________ perfmon2-devel mailing list perfmon2-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/perfmon2-devel
