Provided by: trace-cmd_1.0.3-0ubuntu2_i386
trace-cmd-extract - extract out the data from the Ftrace Linux tracer.
trace-cmd extract [OPTIONS]
The trace-cmd(1) extract is usually used after trace-cmd-start(1) and
trace-cmd-stop(1). It can be used after the Ftrace tracer has been
started manually through the Ftrace pseudo file system.
The extract command creates a trace.dat file that can be used by
trace-cmd-report(1) to read from. It reads the kernel internal ring
buffer to produce the trace.dat file.
Although extract does not start any traces, some of the plugins
require just reading the output in ASCII format. These are the
latency tracers, since the latency tracers have a separate internal
buffer. The plugin option is therefore only necessary for the
wakeup, wakeup-rt, irqsoff, preemptoff and preemptirqsoff plugins.
With out this option, the extract command will extract from the internal
If a latency tracer is being extracted, and the -p option is used,
then there are some Ftrace options that can change the format. This
will update those options before extracting. To see the list of
options see trace-cmd-list. To enable an option, write its name, to
disable the option append the characters no to it. For example:
noprint-parent will disable the print-parent option that prints the
parent function in printing a function event.
By default, the extract command will create a trace.dat file. This
option will change where the file is written to.
trace-cmd(1), trace-cmd-record(1), trace-cmd-report(1),
trace-cmd-start(1), trace-cmd-stop(1), trace-cmd-reset(1),
trace-cmd-split(1), trace-cmd-list(1), trace-cmd-listen(1)
Written by Steven Rostedt, <firstname.lastname@example.org>
Copyright (C) 2010 Red Hat, Inc. Free use of this software is granted
under the terms of the GNU Public License (GPL).