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
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),
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).