reading PMU counts with perf leader sampling and perf script

[Omar Awile <omar.awile@cern.ch>]

Hello,

I’ve been trying to get periodic readouts of PMU event counts using perf record (similar to what perf stat -I does but with a higher precision than 10ms).

For this I thought I could use leader sampling with ref_cycles and the events I am targeting.

For example something like this:

$ perf record -P -c 2000000 -e '{cycles,instructions,branch-misses}:S' — ./workload

This seems to read out the sample values for the other events whenever the cycle event is sampled.

The next step would be for me to use perf script and a little python script to get the event counts but I can’t seem to find a way to do this. Can someone point me in the right direction?

perf report seems to be able to read these samples but they are shown only as aggregates. Also, perf script would allow me to process/analyze the data myself. If this is currently not possible, how would I go about adding the missing functionality in perf script?

Thank you,

Omar Awile

--  
Omar Awile, Ph.D.
Systems Performance Engineer
CERN - 513/R-046