I used the following command to extract backtraces leading to user level L3-misses in a simple evince benchmark: As it is clear, the sampling period is quite large (10000 events between consecutive samples). For this experiment, the output of perf script had some samples similar to this one: At the bottom of the backtrace, there is a symbol called [unknown],
Tag: performancecounter
definition of linux perf cache-misses event?
I am trying to use linux perf to profile cache performance. perf list shows there is a cache-misses event. However, what’s the definition of this “cache-misses” event? Is it one of L1D/L1i cache, L2 cache or L3 cache? Thanks! Answer The cache-misses event corresponds to the misses in the last level cache (LLC). Note that this is an architectural performance
Which perf events can use PEBS?
I want to understand which events can have the precise modifier on my CPU (Sandy Bridge). Intel Software Developer’s Manual (Table 18-32. PEBS Performance Events for Intel Microarchitecture Code Name Sandy Bridge) contains only the following events: INST_RETIRED, UOPS_RETIRED, BR_INST_RETIRED, BR_MISP_RETIRED, MEM_UOPS_RETIRED, MEM_LOAD_UOPS_RETIRED, MEM_LOAD_UOPS_LLC_HIT_RETIRED. And SandyBridge_core_V15.json lists the same events with PEBS > 0. However there are some examples of
Use linux perf utility to report counters every second like vmstat
There is perf command-linux utility in Linux to access hardware performance-monitoring counters, it works using perf_events kernel subsystems. perf itself has basically two modes: perf record/perf top to record sampling profile (the sample is for example every 100000th cpu clock cycle or executed command), and perf stat mode to report total count of cycles/executed commands for the application (or for