libpfm_intel_snbep_unc_ha — support for Intel Sandy Bridge-EP Home Agent (HA) uncore PMU


#include <perfmon/pfmlib.h>

PMU name: snbep_unc_ha
PMU desc: Intel Sandy Bridge-EP HA uncore PMU


The library supports the Intel Sandy Bridge Home Agent (HA) uncore PMU. This PMU model only exists on Sandy Bridge model 45. There is only one Home Agent per processor socket.


The following modifiers are supported on Intel Sandy Bridge C-Box uncore PMU:


Invert the meaning of the event. The counter will now count HA cycles in which the event is not occurring. This is a boolean modifier


Enable edge detection, i.e., count only when there is a state transition from no occurrence of the event to at least one occurrence. This modifier must be combined with a threshold modifier (t) with a value greater or equal to one.  This is a boolean modifier.


Set the threshold value. When set to a non-zero value, the counter counts the number of HA cycles in which the number of occurrences of the event is greater or equal to the threshold.  This is an integer modifier with values in the range [0:255].


Stephane Eranian <>


August, 2012 Linux Programmer's Manual