On Mon, Mar 21, 2011 at 10:43 AM, 陳韋任 <che...@iis.sinica.edu.tw> wrote: > Hi, > > Ah, I see. There is a comment at kernel/perf_event.c: > > /* > * perf event paranoia level: > * -1 - not paranoid at all > * 0 - disallow raw tracepoint access for unpriv > * 1 - disallow cpu events for unpriv > * 2 - disallow kernel profiling for unpriv > */ > I doubt this is the problem.
You need to make sure you have a kernel that supports PEBS. To do that, you can check the syslog. dmesg | fgrep PEBS should do it. > But I have another question. `perf list` give me no such information > about PBES, so I have to try and error. Is there a better way to know > which events can be applied whith modifier "p"? > perf list does not give you this information because it does not know. That is one of the many caveats of generic PMU events. You don't know on what they are mapped to, thus it is hard to go back to the PMU documentation to figure out PEBS. The Intel documentation provides the information as to what event supports PEBS (precise sampling), though it is known to miss some. libbpfm4 does maintain this information. It won't let you enable precise sampling (precise=) if the event does not support PEBS. > Regards, > chenwj > > -- > Wei-Ren Chen (陳韋任) > Parallel Processing Lab, Institute of Information Science, > Academia Sinica, Taiwan (R.O.C.) > Tel:886-2-2788-3799 #1667 > > ------------------------------------------------------------------------------ > Colocation vs. Managed Hosting > A question and answer guide to determining the best fit > for your organization - today and in the future. > http://p.sf.net/sfu/internap-sfd2d > _______________________________________________ > perfmon2-devel mailing list > perfmon2-devel@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/perfmon2-devel > ------------------------------------------------------------------------------ Colocation vs. Managed Hosting A question and answer guide to determining the best fit for your organization - today and in the future. http://p.sf.net/sfu/internap-sfd2d _______________________________________________ perfmon2-devel mailing list perfmon2-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/perfmon2-devel
