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, <rostedt@goodmis.org[1]>

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                        04/07/2024             TRACE-CMD-SNAPSHOT(1)