NAME

       trace-cmd-show - show the contents of the Ftrace Linux kernel tracing buffer.

SYNOPSIS

       trace-cmd show [OPTIONS]

DESCRIPTION

       The trace-cmd(1) show displays the contents of one of the Ftrace Linux kernel tracing
       files: trace, snapshot, or trace_pipe. It is basically the equivalent of doing:

           cat /sys/kernel/debug/tracing/trace

OPTIONS

       -p
           Instead of displaying the contents of the "trace" file, use the "trace_pipe" file. The
           difference between the two is that the "trace" file is static. That is, if tracing is
           stopped, the "trace" file will show the same contents each time.

               The "trace_pipe" file is a consuming read, where a read of the file
               will consume the output of what was read and it will not read the
               same thing a second time even if tracing is stopped. This file
               als will block. If no data is available, trace-cmd show will stop
               and wait for data to appear.

       -s
           Instead of reading the "trace" file, read the snapshot file. The snapshot is made by
           an application writing into it and the kernel will perform as swap between the
           currently active buffer and the current snapshot buffer. If no more swaps are made,
           the snapshot will remain static. This is not a consuming read.

       -c cpu
           Read only the trace file for a specified CPU.

       -f
           Display the full path name of the file that is being displayed.

       -B buf
           If a buffer instance was created, then the -B option will access the files associated
           with the given buffer.

       --tracing_on
           Show if tracing is on for the given instance.

       --current_tracer
           Show what the current tracer is.

       --buffer_size
           Show the current buffer size (per-cpu)

       --buffer_total_size
           Show the total size of all buffers.

       --ftrace_filter
           Show what function filters are set.

       --ftrace_notrace
           Show what function disabled filters are set.

       --ftrace_pid
           Show the PIDs the function tracer is limited to (if any).

       --graph_function
           Show the functions that will be graphed.

       --graph_notrace
           Show the functions that will not be graphed.

       --cpumask
           Show the mask of CPUs that tracing will trace.

SEE ALSO

       trace-cmd(1), trace-cmd-record(1), trace-cmd-report(1), trace-cmd-start(1),
       trace-cmd-extract(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

       git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/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

                                            05/06/2015                          TRACE-CMD-SHOW(1)