1TRACE-CMD-RESET(1) TRACE-CMD-RESET(1)
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6 trace-cmd-reset - turn off all Ftrace tracing to bring back full
7 performance
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10 trace-cmd reset [OPTIONS]
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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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24 Please note that the order that options are specified on the command
25 line is significant. See EXAMPLES.
26 -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 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 trace-cmd reset -b 1
37 The buffer instance affected is the one (or ones) specified by the most
39 recently preceding *-B*, *-t*, or *-a* option:
40 When used after *-B*, resizes the buffer instance that precedes it on
42 the command line.
43 When used after *-a*, resizes all buffer instances except the top one.
45 When used after *-t* or before any *-B* or *-a*, resizes the top
47 instance.
48 -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).
55 -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.
60 -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 -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.
71
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:
76 trace-cmd reset -B instance-one -b 4096 -B instance-two -d
78 Delete all instance buffers. Top level instance remains unaffected:
80 trace-cmd reset -a -d
82 Delete all instance buffers and also reset the top instance:
84 trace-cmd reset -t -a -d
86 Invalid. This command implies an attempt to delete the top instance:
88 trace-cmd reset -a -t -d
90 Reset the top instance and set its per-cpu buffer size to 1024kb. If
92 any instance buffers exist, they will be unaffected:
93 trace-cmd reset -b 1024
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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)
100
102 Written by Steven Rostedt, <rostedt@goodmis.org[1]>
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105 git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/trace-cmd.git
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108 Copyright (C) 2010 Red Hat, Inc. Free use of this software is granted
109 under the terms of the GNU Public License (GPL).
110
112 1. rostedt@goodmis.org
113 mailto:rostedt@goodmis.org
114 08/07/2019 TRACE-CMD-RESET(1)