Ken, On Sat, Dec 23, 2006 at 01:20:08PM +0100, [EMAIL PROTECTED] wrote: > > I realize that this is an old thread, but it seems quite relevant to > me now... My apologies if I shouldn't be replying on old threads... > > Citeren Stephane Eranian <[EMAIL PROTECTED]>: > > >Kevin, > > > >On Thu, Aug 24, 2006 at 01:23:47PM -0500, Kevin Corry wrote: > >>On Thu August 24 2006 10:44 am, Stephane Eranian wrote: > >>> On Thu, Aug 24, 2006 at 10:10:17AM -0500, Kevin Corry wrote: > >>> > I've definitely been able to count things on P4 with pfmon. > >>> > >>> That's excellent. No offense for the comment, I think I was still under > >>> the impression it was very preliminary (from your own comments) > >>> and that it was not counting yet. > >>> > >>> Obviously, I was wrong, my apologies. > >> > >>Not a problem. You're right that I did mention that the support is not > >>complete - there are features of the P4 PMU that I still want to add > >>support > >>for: event filtering, event tagging, and event cascading. But the > >>code that's > >>there now is useable for basic event counting. > >> > >Ok, so you are saying that basic counting (and sampling) should work > > fine then. > >That is already quite an accomlishment given the complexity of the P4. > > > > As some of you may have noticed in a thread on the PAPI mailinglist, > counts on P4 don't seem right. > I've counted instructions for SPEC CPU2000 using PIN (a dynamic > instrumentator) and compared them with papiex (latest version, > together with latest perfctr patch) and an Fedora Core 4 Linux / Intel > Pentium 4 machine (see attachment).? > For some benchmarks the counts are quite similar, but for others, they > are way of. Mesa is a nice example of this: papiex counts almost > 7*10^9 instructions more, or 2.5% more than PIN does ! The PIN counts > have been validated using another instrumentator (DIOTA), and counts > using perfex on an AMD Athlon machine. Even for mesa, counts didn't > differ more than 300,000 instructions. > Did you try other events? Also PIN only counts user level instructions. did you make sure your measurements were setup to count only at user level?
Also have you tried in system-wide mode, just to verify that there is nothing wrong with the PMU context switch code. As for instr_completed, I have never been able to measure it correctly. There may be unpublished constraints on this event which libpfm does not know about. -- -Stephane _______________________________________________ perfmon mailing list [email protected] http://www.hpl.hp.com/hosted/linux/mail-archives/perfmon/
