Documentation/trace-cmd-snapshot.1.txt

TRACE-CMD-SNAPSHOT(1)
===================

NAME
----
trace-cmd-snapshot - take, reset, free, or show a Ftrace kernel snapshot

SYNOPSIS
--------
*trace-cmd snapshot* ['OPTIONS']

DESCRIPTION
-----------
The trace-cmd(1) snapshot controls or displays the Ftrace Linux kernel
snapshot feature (if the kernel supports it). This is useful to "freeze"
an instance of a live trace but without stopping the trace.

  trace-cmd start -p function
  trace-cmd snapshot -s
  trace-cmd snapshot
 [ dumps the content of buffer at 'trace-cmd snapshot -s' ]
  trace-cmd snapshot -s
  trace-cmd snapshot
 [ dumps the new content of the buffer at the last -s operation ]

OPTIONS
-------
*-s*::
    Take a snapshot of the currently running buffer.

*-r*::
    Clear out the buffer.

*-f*::
    Free the snapshot buffer. The buffer takes up memory inside the
    kernel. It is best to free it when not in use. The first -s
    operation will allocate it if it is not already allocated.

*-c* 'cpu'::
    Operate on a per cpu snapshot (may not be fully supported by all kernels)

*-B* 'buf'::
    If a buffer instance was created, then the *-B* option will operate on
    the snapshot within the buffer.
    

SEE ALSO
--------
trace-cmd(1), trace-cmd-record(1), trace-cmd-report(1), trace-cmd-start(1),
trace-cmd-extract(1), trace-cmd-reset(1), trace-cmd-split(1),
trace-cmd-list(1), trace-cmd-listen(1)

AUTHOR
------
Written by Steven Rostedt, <rostedt@goodmis.org>

RESOURCES
---------
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/trace-cmd.git

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