bcall@snowball trafficserver$ sudo opcontrol --start-daemon
WARNING: Deprecated config file /etc/modprobe.conf, all config files belong into /etc/modprobe.d/.
Detected stale lock file. Removing.
Using default event: CPU_CLK_UNHALTED:100000:0:1:1
Using 2.6+ OProfile kernel interface.
Using log file /var/lib/oprofile/samples/oprofiled.log
Daemon started.

bcall@snowball trafficserver$ sudo opcontrol --status
Daemon running: pid 29524
Separate options: library
vmlinux file: none
Image filter: none
Call-graph depth: 6

1. 1. run some benchmark
      bcall@snowball trafficserver$ sudo opcontrol -s; sleep 60; sudo opcontrol -t
      Profiler running.