Manual: trace-cmd-snapshot

TRACE-CMD-SNAPSHOT(1)				      libtracefs Manual				       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, 

RESOURCES
       https://git.kernel.org/pub/scm/utils/trace-cmd/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).

NOTES
	1. rostedt@goodmis.org
	   mailto:rostedt@goodmis.org

libtracefs						 01/22/2026				       TRACE-CMD-SNAPSHOT(1)