trace-cmd-extract - Man Page

trace-cmd extract [Options]

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​.

-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

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)

Written by Steven Rostedt, <rostedt@goodmis​.org​^[1]>

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

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

1.

rostedt@goodmis.org
mailto:rostedt@goodmis.org

trace-cmd(1), trace-cmd-agent(1), trace-cmd-attach(1), trace-cmd-check-events(1), trace-cmd-clear(1), trace-cmd.dat.v6(5), trace-cmd.dat.v7(5), trace-cmd-hist(1), trace-cmd-list(1), trace-cmd-listen(1), trace-cmd-mem(1), trace-cmd-options(1), trace-cmd-record(1), trace-cmd-report(1), trace-cmd-reset(1), trace-cmd-restore(1), trace-cmd-set(1), trace-cmd-show(1), trace-cmd-snapshot(1), trace-cmd-split(1), trace-cmd-stack(1), trace-cmd-start(1), trace-cmd-stat(1), trace-cmd-stop(1).