Will, On Tue, Nov 28, 2006 at 10:11:33AM -0500, William Cohen wrote: > OProfile splits the perfmon hardware between the two logical processor when > the P4 has hyperthreading enabled and it appears that Perfmon2 does the > same. On OProfile the number of events supported in hyperthreaded mode is > considerably reduced because the P4 in HT doesn't track which logical > processor an event came from. However, libpfm doesn't seem to do this for > hyperthreading. How does perfmon2 keep the events from the logical > processors separate? Isn't this going to present a problem for per thread > event counting? > The current libpfm for P4 does not take into account HT. I have not looked at this problem in detail myself, maybe Kevin has more information. Where is the information concerning event restrictions in HT mode?
I do not think this would be too hard to add to libpfm. -- -Stephane _______________________________________________ perfmon mailing list [email protected] http://www.hpl.hp.com/hosted/linux/mail-archives/perfmon/
