1TRACE-CMD-SNAPSHOT(1)          libtracefs Manual         TRACE-CMD-SNAPSHOT(1)
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NAME

6       trace-cmd-snapshot - take, reset, free, or show a Ftrace kernel
7       snapshot
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SYNOPSIS

10       trace-cmd snapshot [OPTIONS]
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DESCRIPTION

13       The trace-cmd(1) snapshot controls or displays the Ftrace Linux kernel
14       snapshot feature (if the kernel supports it). This is useful to
15       "freeze" an instance of a live trace but without stopping the trace.
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17            trace-cmd start -p function
18            trace-cmd snapshot -s
19            trace-cmd snapshot
20           [ dumps the content of buffer at 'trace-cmd snapshot -s' ]
21            trace-cmd snapshot -s
22            trace-cmd snapshot
23           [ dumps the new content of the buffer at the last -s operation ]
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OPTIONS

26       -s
27           Take a snapshot of the currently running buffer.
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29       -r
30           Clear out the buffer.
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32       -f
33           Free the snapshot buffer. The buffer takes up memory inside the
34           kernel. It is best to free it when not in use. The first -s
35           operation will allocate it if it is not already allocated.
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37       -c cpu
38           Operate on a per cpu snapshot (may not be fully supported by all
39           kernels)
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41       -B buf
42           If a buffer instance was created, then the -B option will operate
43           on the snapshot within the buffer.
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SEE ALSO

46       trace-cmd(1), trace-cmd-record(1), trace-cmd-report(1),
47       trace-cmd-start(1), trace-cmd-extract(1), trace-cmd-reset(1),
48       trace-cmd-split(1), trace-cmd-list(1), trace-cmd-listen(1)
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AUTHOR

51       Written by Steven Rostedt, <rostedt@goodmis.org[1]>
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RESOURCES

54       https://git.kernel.org/pub/scm/utils/trace-cmd/trace-cmd.git/
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COPYING

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

61        1. rostedt@goodmis.org
62           mailto:rostedt@goodmis.org
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66libtracefs                        04/15/2022             TRACE-CMD-SNAPSHOT(1)
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