What: /sys/devices/cpu/events/ /sys/devices/cpu/events/branch-misses /sys/devices/cpu/events/cache-references /sys/devices/cpu/events/cache-misses /sys/devices/cpu/events/stalled-cycles-frontend /sys/devices/cpu/events/branch-instructions /sys/devices/cpu/events/stalled-cycles-backend /sys/devices/cpu/events/instructions /sys/devices/cpu/events/cpu-cycles Date: 2013/01/08 Contact: Linux kernel mailing list Description: Generic performance monitoring events A collection of performance monitoring events that may be supported by many/most CPUs. These events can be monitored using the 'perf(1)' tool. The contents of each file would look like: event=0xNNNN where 'N' is a hex digit and the number '0xNNNN' shows the "raw code" for the perf event identified by the file's "basename". What: /sys/bus/event_source/devices//events/ Date: 2014/02/24 Contact: Linux kernel mailing list Description: Per-pmu performance monitoring events specific to the running system Each file (except for some of those with a '.' in them, '.unit' and '.scale') in the 'events' directory describes a single performance monitoring event supported by the . The name of the file is the name of the event. File contents: [=][,[=]]... Where is one of the terms listed under /sys/bus/event_source/devices//format/ and is a number is base-16 format with a '0x' prefix (lowercase only). If a is specified alone (without an assigned value), it is implied that 0x1 is assigned to that . Examples (each of these lines would be in a separate file): event=0x2abc event=0x423,inv,cmask=0x3 domain=0x1,offset=0x8,starting_index=0xffff domain=0x1,offset=0x8,core=? Each of the assignments indicates a value to be assigned to a particular set of bits (as defined by the format file corresponding to the ) in the perf_event structure passed to the perf_open syscall. In the case of the last example, a value replacing "?" would need to be provided by the user selecting the particular event. This is referred to as "event parameterization". Event parameters have the format 'param=?'. What: /sys/bus/event_source/devices//events/.unit Date: 2014/02/24 Contact: Linux kernel mailing list Description: Perf event units A string specifying the English plural numerical unit that (once multiplied by .scale) represents. Example: Joules What: /sys/bus/event_source/devices//events/.scale Date: 2014/02/24 Contact: Linux kernel mailing list Description: Perf event scaling factors A string representing a floating point value expressed in scientific notation to be multiplied by the event count received from the kernel to match the unit specified in the .unit file. Example: 2.3283064365386962890625e-10 This is provided to avoid performing floating point arithmetic in the kernel.