execsnoop_example.txt

Demonstrations of execsnoop, the Linux BPF/bpftrace version.


Tracing all new process execution (via exec()):

# execsnoop.bt
Attaching 3 probes...
TIME(ms)   PID   ARGS
2460       3466  ls --color=auto -lh execsnoop.bt execsnoop.bt.0 execsnoop.bt.1
3996       3467  man ls
4005       3473  preconv -e UTF-8
4005       3473  preconv -e UTF-8
4005       3473  preconv -e UTF-8
4005       3473  preconv -e UTF-8
4005       3473  preconv -e UTF-8
4005       3474  tbl
4005       3474  tbl
4005       3474  tbl
4005       3474  tbl
4005       3474  tbl
4005       3476  nroff -mandoc -rLL=193n -rLT=193n -Tutf8
4005       3476  nroff -mandoc -rLL=193n -rLT=193n -Tutf8
4005       3476  nroff -mandoc -rLL=193n -rLT=193n -Tutf8
4005       3476  nroff -mandoc -rLL=193n -rLT=193n -Tutf8
4005       3476  nroff -mandoc -rLL=193n -rLT=193n -Tutf8
4006       3479  pager  -rLL=193n
4006       3479  pager  -rLL=193n
4006       3479  pager  -rLL=193n
4006       3479  pager  -rLL=193n
4006       3479  pager  -rLL=193n
4007       3481  locale charmap
4008       3482  groff -mtty-char -Tutf8 -mandoc -rLL=193n -rLT=193n
4009       3483  troff -mtty-char -mandoc -rLL=193n -rLT=193n -Tutf8

The output begins by showing an "ls" command, and then the process execution
to serve "man ls". The same exec arguments appear multiple times: in this case
they are failing as the $PATH variable is walked, until one finally succeeds.

This tool can be used to discover unwanted short-lived processes that may be
causing performance issues such as latency perturbations.


There is another version of this tool in bcc: https://github.com/iovisor/bcc
The bcc version provides more fields and command line options.