prf(7)

prf -- operating system profiler

Description

The special file /dev/prf provides access to activity information in the operating system. The profiler commands load the measurement facility with text addresses to be monitored. Reading the file returns these addresses and a set of counters indicative of activity between adjacent text addresses.

The recording mechanism is driven by the system clock and samples the program counter at line frequency. Samples that catch the operating system are matched against the stored text addresses and increment corresponding counters for later processing.

The /dev/prf file is a pseudo-device with no associated hardware.

NOTE: If the prf device is not configured into the kernel, to turn it on you must edit /etc/conf/sdevice.d/prf, change the second field from N to Y, and reconfigure the kernel.

When the profiler is turned on, loadable modules are locked into memory and cannot be unloaded. Subsequently loaded modules will also be locked until profiling is disabled.

Files

/dev/prf

References

profiler(1M)