TRACE-CMD-EXTRACT(1) libtracefs Manual TRACE-CMD-EXTRACT(1)
NAME
trace-cmd-extract - extract out the data from the Ftrace Linux tracer.
SYNOPSIS
trace-cmd extract [OPTIONS]
DESCRIPTION
The trace-cmd(1) extract is usually used after trace-cmd-start(1) and
trace-cmd-stop(1). It can be used after the Ftrace tracer has been
started manually through the Ftrace pseudo file system.
The extract command creates a trace.dat file that can be used by
trace-cmd-report(1) to read from. It reads the kernel internal ring
buffer to produce the trace.dat file.
OPTIONS
-p plugin
Although extract does not start any traces, some of the plugins
require just reading the output in ASCII format. These are the
latency tracers, since the latency tracers have a separate internal
buffer. The plugin option is therefore only necessary for the
wakeup, wakeup-rt, irqsoff, preemptoff and preemptirqsoff plugins.
With out this option, the extract command will extract from the internal
Ftrace buffers.
-O option
If a latency tracer is being extracted, and the -p option is used,
then there are some Ftrace options that can change the format. This
will update those options before extracting. To see the list of
options see trace-cmd-list. To enable an option, write its name, to
disable the option append the characters no to it. For example:
noprint-parent will disable the print-parent option that prints the
parent function in printing a function event.
-o outputfile
By default, the extract command will create a trace.dat file. This
option will change where the file is written to.
-s
Extract from the snapshot buffer (if the kernel supports it).
--date
This is the same as the trace-cmd-record(1) --date option, but it
does cause the extract routine to disable all tracing. That is, the
end of the extract will perform something similar to
trace-cmd-reset(1).
-B buffer-name
If the kernel supports multiple buffers, this will extract the
trace for only the given buffer. It does not affect any other
buffer. This may be used multiple times to specify different
buffers. When this option is used, the top level instance will not
be extracted unless -t is given.
-a
Extract all existing buffer instances. When this option is used,
the top level instance will not be extracted unless -t is given.
-t
Extracts the top level instance buffer. Without the -B or -a option
this is the same as the default. But if -B or -a is used, this is
required if the top level instance buffer should also be extracted.
--verbose[=level]
Set the log level. Supported log levels are "none", "critical",
"error", "warning", "info", "debug", "all" or their identifiers
"0", "1", "2", "3", "4", "5", "6". Setting the log level to
specific value enables all logs from that and all previous levels.
The level will default to "info" if one is not specified.
Example: enable all critical, error and warning logs
trace-cmd extract --verbose=warning
SEE ALSO
trace-cmd(1), trace-cmd-record(1), trace-cmd-report(1),
trace-cmd-start(1), trace-cmd-stop(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 04/08/2024 TRACE-CMD-EXTRACT(1)
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