TPROF(8) BSD System Manager's Manual TPROF(8)NAMEtprof — record tprof profiling samples
SYNOPSIStprof [-c] [-o file] command ...
DESCRIPTION
The tprof is a sampling based profiler.
tprof utility makes the kernel driver start profiling, executes the spec‐
ified command, keeps recording samples from the kernel driver until the
command finishes, and reports statistics to the standard error.
The tprof pseudo driver and a suitable backend should be loaded before‐
hand.
The tprof utility accepts the following options.
-o file Write the collected samples to the file named file. The
default is “tprof.out”.
-c Write the collected samples to the standard output. Note that
the output is a binary stream.
EXAMPLES
The following command profiles the system during 1 second and shows the
top-10 kernel functions which likely consumed CPU cycles.
tprof-c sleep 1 2>/dev/null | tpfmt -skCLP | head -10
DIAGNOSTICS
The tprof utility reports the following statistics about the activities
of the tprof pseudo driver.
sample The number of samples collected and prepared for user‐
land consumption.
overflow The number of samples dropped because the per-CPU buffer
was full.
buf The number of buffers successfully prepared for userland
consumption.
emptybuf The number of buffers which have been dropped because
they were empty.
dropbuf The number of buffers dropped because the number of buf‐
fers kept in the kernel exceeds the limit.
dropbuf_samples The number of samples dropped because the buffers con‐
taining the samples were dropped.
SEE ALSOtpfmt(1), tprof(4)AUTHORS
The tprof utility is written by YAMAMOTO Takashi.
CAVEATS
The contents and representation of recorded samples are undocumented and
will likely be changed for future releases of NetBSD in an incompatible
way.
BSD November 26, 2011 BSD