2. OProfile perf_events profiling mode

As of release 0.9.8, OProfile now includes the ability to profile a single process versus the system-wide technique of legacy OProfile. With this new technique, the operf program is used to control profiling instead of the opcontrol script and oprofiled daemon of leagacy mode. Also, operf does not require the special OProfile kernel driver that legacy mode does; instead, it interfaces with the kernel to collect samples via the Linux Kernel Performance Events Subsystem (hereafter referred to as "perf_events"). Using operf to profile a single process can be done as a normal user; however, root authority is required to run operf in system-wide profiling mode.

Note 1

The same OProfile post-processing tools are used whether you collect your profile with operf or opcontrol.

Note 2

Some older processor models are not supported by the underlying perf_events kernel and, thus, are not supported by operf. If you receive the message
  Your kernel's Performance Events Subsystem does not support your processor type
when attempting to use operf, try profiling with opcontrol to see if your processor type may be supported by OProfile's legacy mode.