# trace-cmd-extract

## 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
    


## 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
    


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