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

6       trace-cmd-reset - turn off all Ftrace tracing to bring back full
7       performance
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SYNOPSIS

10       trace-cmd reset [OPTIONS]
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DESCRIPTION

13       The trace-cmd(1) reset command turns off all tracing of Ftrace. This
14       will bring back the performance of the system before tracing was
15       enabled. This is necessary since trace-cmd-record(1), trace-cmd-stop(1)
16       and trace-cmd-extract(1) do not disable the tracer, event after the
17       data has been pulled from the buffers. The rational is that the user
18       may want to manually enable the tracer with the Ftrace pseudo file
19       system, or examine other parts of Ftrace to see what trace-cmd did.
20       After the reset command happens, the data in the ring buffer, and the
21       options that were used are all lost.
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OPTIONS

24       Please note that the order that options are specified on the command
25       line is significant. See EXAMPLES.
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27       -b buffer_size
28           When the kernel boots, the Ftrace ring buffer is of a minimal size
29           (3 pages per CPU). The first time the tracer is used, the ring
30           buffer size expands to what it was set for (default 1.4 Megs per
31           CPU).
32
33               If no more tracing is to be done, this option allows you to shrink the
34               ring buffer down to free up available memory.
35
36               trace-cmd reset -b 1
37
38               The buffer instance affected is the one (or ones) specified by the most
39               recently preceding *-B*, *-t*, or *-a* option:
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41               When used after *-B*, resizes the buffer instance that precedes it on
42               the command line.
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44               When used after *-a*, resizes all buffer instances except the top one.
45
46               When used after *-t* or before any *-B* or *-a*, resizes the top
47               instance.
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49       -B buffer-name
50           If the kernel supports multiple buffers, this will reset the trace
51           for only the given buffer. It does not affect any other buffer.
52           This may be used multiple times to specify different buffers. The
53           top level buffer will not be reset if this option is given (unless
54           the -t option is also supplied).
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56       -a
57           Reset the trace for all existing buffer instances. When this option
58           is used, the top level instance will not be reset unless -t is
59           given.
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61       -d
62           This option deletes the instance buffer(s) specified by the most
63           recently preceding -B or -a option. Because the top-level instance
64           buffer cannot be deleted, it is invalid to use this immediatly
65           following -t or prior to any -B or -a option on the command line.
66
67       -t
68           Resets the top level instance buffer. Without the -B or -a option
69           this is the same as the default. But if -B or -a is used, this is
70           required if the top level instance buffer should also be reset.
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EXAMPLES

73       Reset tracing for instance-one and set its per-cpu buffer size to
74       4096kb. Also deletes instance-two. The top level instance and any other
75       instances remain unaffected:
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77           trace-cmd reset -B instance-one -b 4096 -B instance-two -d
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79       Delete all instance buffers. Top level instance remains unaffected:
80
81           trace-cmd reset -a -d
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83       Delete all instance buffers and also reset the top instance:
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85           trace-cmd reset -t -a -d
86
87       Invalid. This command implies an attempt to delete the top instance:
88
89           trace-cmd reset -a -t -d
90
91       Reset the top instance and set its per-cpu buffer size to 1024kb. If
92       any instance buffers exist, they will be unaffected:
93
94           trace-cmd reset -b 1024
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SEE ALSO

97       trace-cmd(1), trace-cmd-record(1), trace-cmd-report(1),
98       trace-cmd-start(1), trace-cmd-stop(1), trace-cmd-extract(1),
99       trace-cmd-split(1), trace-cmd-list(1), trace-cmd-listen(1)
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AUTHOR

102       Written by Steven Rostedt, <rostedt@goodmis.org[1]>
103

RESOURCES

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

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

112        1. rostedt@goodmis.org
113           mailto:rostedt@goodmis.org
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117libtracefs                        07/23/2022                TRACE-CMD-RESET(1)
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