TRACE-CMD-EXTRACT(1)                                    TRACE-CMD-EXTRACT(1)

NAME         top

       trace-cmd-extract - extract out the data from the Ftrace Linux

SYNOPSIS         top

       trace-cmd extract [OPTIONS]

DESCRIPTION         top

       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.

OPTIONS         top

       -p plugin
           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

               With out this option, the extract command will extract from the internal
               Ftrace buffers.

       -O option
           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

       -o outputfile
           By default, the extract command will create a trace.dat file.
           This option will change where the file is written to.

           Extract from the snapshot buffer (if the kernel supports it).

           This is the same as the trace-cmd-record(1) --date option, but it
           does cause the extract routine to disable all tracing. That is,
           the end of the extract will perform something similar to

       -B buffer-name
           If the kernel supports multiple buffers, this will extract the
           trace for only the given buffer. It does not affect any other
           buffer. This may be used multiple times to specify different
           buffers. When this option is used, the top level instance will
           not be extracted unless -t is given.

           Extract all existing buffer instances. When this option is used,
           the top level instance will not be extracted unless -t is given.

           Extracts the top level instance buffer. Without the -B or -a
           option this is the same as the default. But if -B or -a is used,
           this is required if the top level instance buffer should also be

SEE ALSO         top

       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)

AUTHOR         top

       Written by Steven Rostedt, <[1]>

RESOURCES         top


COPYING         top

       Copyright (C) 2010 Red Hat, Inc. Free use of this software is granted
       under the terms of the GNU Public License (GPL).

NOTES         top


COLOPHON         top

       This page is part of the trace-cmd (a front-end for Ftrace) project.
       Information about the project can be found at [unknown -- if you
       know, please contact] If you have a bug report for
       this manual page, send it to Steven Rostedt <>.
       This page was obtained from the project's upstream Git repository 
       on 2017-03-13.  If you discover any rendering problems in this HTML
       version of the page, or you believe there is a better or more up-to-
       date source for the page, or you have corrections or improvements to
       the information in this COLOPHON (which is not part of the original
       manual page), send a mail to

                                 07/22/2015             TRACE-CMD-EXTRACT(1)