trace-cmd-snapshot(1) — Linux manual page
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
COLOPHON
This page is part of the trace-cmd (a front-end for Ftrace)
project. Information about the project can be found at
⟨https://www.trace-cmd.org/⟩. If you have a bug report for this
manual page, see ⟨https://www.trace-cmd.org/⟩. This page was
obtained from the project's upstream Git repository
⟨https://git.kernel.org/pub/scm/utils/trace-cmd/trace-cmd.git⟩ on
2024-06-14. (At that time, the date of the most recent commit
that was found in the repository was 2024-02-22.) 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 man-pages@man7.org