trace-cmd

Display the status of tracing system

$ trace-cmd stat

List available tracers

$ trace-cmd list -t

Start tracing with a specific plugin

$ trace-cmd start -p [timerlat|osnoise|hwlat|blk|mmiotrace|function_graph|wakeup_dl|wakeup_rt|wakeup|function|nop]

View the trace output

$ trace-cmd show

Stop the tracing but retain the buffers

$ trace-cmd stop

Clear the trace buffers

$ trace-cmd clear

Clear the trace buffers and stop tracing

$ trace-cmd reset

trace-cmd COMMAND [OPTIONS]

The trace-cmd(1) command interacts with the Ftrace tracer that is built inside the Linux kernel. It interfaces with the Ftrace specific files found in the debugfs file system under the tracing directory. A COMMAND must be specified to tell trace-cmd what to do.

record  - record a live trace and write a trace.dat file to the
          local disk or to the network.

report  - reads a trace.dat file and converts the binary data to a
          ASCII text readable format.

hist    - show a histogram of the events.

stat    - show tracing (ftrace) status of the running system

options - list the plugin options that are available to *report*

start   - start the tracing without recording to a trace.dat file.

stop    - stop tracing (only disables recording, overhead of tracer
          is still in effect)

restart - restart tracing from a previous stop (only effects recording)

extract - extract the data from the kernel buffer and create a trace.dat
          file.

reset   - disables all tracing and gives back the system performance.
          (clears all data from the kernel buffers)

split   - splits a trace.dat file into smaller files.

list    - list the available plugins or events that can be recorded.

listen  - open up a port to listen for remote tracing connections.

restore - restore the data files of a crashed run of trace-cmd record

stack   - run and display the stack tracer

check-events - parse format strings for all trace events and return
               whether all formats are parseable

-h, --help

Display the help text.

Other options see the man page for the corresponding command.

git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/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-record(1), trace-cmd-report(1), trace-cmd-hist(1), trace-cmd-start(1), trace-cmd-stop(1), trace-cmd-extract(1), trace-cmd-reset(1), trace-cmd-restore(1), trace-cmd-stack(1), trace-cmd-split(1), trace-cmd-list(1), trace-cmd-listen(1), trace-cmd.dat(5), trace-cmd-check-events(1) trace-cmd-stat(1)

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