cachestat.bt

cachestat.bt is a bpftrace script that retrieves from the kernel the pagecache miss and hits. It will print to the terminal at a designated interval the number of hits and misses during the interval, percentage of hits and a time stamp.

Usage ./cachestat.bt : Is the time period in seconds for gathering the cache hits and miss, default is 5 seconds. : How many time intervals to present. Only meaningful when is designated. The default is to run forever.

./cachestat.bt 5 10

Attaching 7 probes...

    Hits      Misses       %hits
  272275       68302          79% 09:29:27
  238210       60501          79% 09:29:33
  260234       67884          79% 09:29:39
  280268       70056          80% 09:29:45
  257868       66952          79% 09:29:51
  241025       60734          79% 09:29:57
  266305       68233          79% 09:30:03
  268565       69923          79% 09:30:09
  265550       69093          79% 09:30:15
  237310       62154          79% 09:30:21

Summary

total hits: 2587612

total miss: 663832

Hit percentage 79