On Thu, Mar 20, 2014 at 10:24 PM, Vince Weaver <vincent.wea...@maine.edu> wrote: > On Thu, 20 Mar 2014, Martin Ichilevici de Oliveira wrote: > >> That program measures the counter for all processes, but I'm >> interested in measuring it only for my program. Since the other >> examples were not working (out of the box) with that event, I decided >> to modify the perf_event_open() call, which was >> >> perf_event_open(&fds[i].hw, -1, 0, -1, 0); > > NorthBridge and Uncore counters are socket-wide. You cannot measure the > values per-process or per-thread. This is a hardware limitation. > Well, this is really a kernel-imposed limitation for a good reason. The counters live in the uncore which is shared by all cores and thus are subject to requests coming from all programs running on the processor socket. Therefore there is NO way to correlate counts you get to your particular application. Thus uncore events are not allowed in per-thread mode.
> ------------------------------------------------------------------------------ > Learn Graph Databases - Download FREE O'Reilly Book > "Graph Databases" is the definitive new guide to graph databases and their > applications. Written by three acclaimed leaders in the field, > this first edition is now available. Download your free book today! > http://p.sf.net/sfu/13534_NeoTech > _______________________________________________ > perfmon2-devel mailing list > perfmon2-devel@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/perfmon2-devel ------------------------------------------------------------------------------ Learn Graph Databases - Download FREE O'Reilly Book "Graph Databases" is the definitive new guide to graph databases and their applications. Written by three acclaimed leaders in the field, this first edition is now available. Download your free book today! http://p.sf.net/sfu/13534_NeoTech _______________________________________________ perfmon2-devel mailing list perfmon2-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/perfmon2-devel
