NAME

       pt-pmp - Aggregate GDB stack traces for a selected program.

SYNOPSIS

       Usage: pt-pmp [OPTIONS] [FILES]

       pt-pmp is a poor man's profiler, inspired by <http://poormansprofiler.org>.  It can create
       and summarize full stack traces of processes on Linux.  Summaries of stack traces can be
       an invaluable tool for diagnosing what a process is waiting for.

RISKS

       Percona Toolkit is mature, proven in the real world, and well tested, but all database
       tools can pose a risk to the system and the database server.  Before using this tool,
       please:

       •   Read the tool's documentation

       •   Review the tool's known "BUGS"

       •   Test the tool on a non-production server

       •   Backup your production server and verify the backups

DESCRIPTION

       pt-pmp performs two tasks: it gets a stack trace, and it summarizes the stack trace.  If a
       file is given on the command line, the tool skips the first step and just aggregates the
       file.

       To summarize the stack trace, the tool extracts the function name (symbol) from each level
       of the stack, and combines them with commas.  It does this for each thread in the output.
       Afterwards, it sorts similar threads together and counts how many of each one there are,
       then sorts them most-frequent first.

       pt-pmp is a read-only tool.  However, collecting GDB stacktraces is achieved by attaching
       GDB to the program and printing stack traces from all threads. This will freeze the
       program for some period of time, ranging from a second or so to much longer on very busy
       systems with a lot of memory and many threads in the program.  In the tool's default usage
       as a MySQL profiling tool, this means that MySQL will be unresponsive while the tool runs,
       although if you are using the tool to diagnose an unresponsive server, there is really no
       reason not to do this.  In addition to freezing the server, there is also some risk of the
       server crashing or performing badly after GDB detaches from it.

OPTIONS

       --binary
           short form: -b; type: string; default: mysqld

           Which binary to trace.

       --help
           Show help and exit.

       --interval
           short form: -s; type: int; default: 0

           Number of seconds to sleep between "--iterations".

       --iterations
           short form: -i; type: int; default: 1

           How many traces to gather and aggregate.

       --lines
           short form: -l; type: int; default: 0

           Aggregate only first specified number of many functions; 0=infinity.

       --pid
           short form: -p; type: int

           Process ID of the process to trace; overrides "--binary".

       --save-samples
           short form: -k; type: string

           Keep the raw traces in this file after aggregation.

       --version
           Show version and exit.

ENVIRONMENT

       This tool does not use any environment variables.

SYSTEM REQUIREMENTS

       This tool requires Bash v3 or newer.  If no backtrace files are given, then gdb is also
       required to create backtraces for the process specified on the command line.

BUGS

       For a list of known bugs, see <http://www.percona.com/bugs/pt-pmp>.

       Please report bugs at <https://jira.percona.com/projects/PT>.  Include the following
       information in your bug report:

       •   Complete command-line used to run the tool

       •   Tool "--version"

       •   MySQL version of all servers involved

       •   Output from the tool including STDERR

       •   Input files (log/dump/config files, etc.)

       If possible, include debugging output by running the tool with "PTDEBUG"; see
       "ENVIRONMENT".

DOWNLOADING

       Visit <http://www.percona.com/software/percona-toolkit/> to download the latest release of
       Percona Toolkit.  Or, get the latest release from the command line:

          wget percona.com/get/percona-toolkit.tar.gz

          wget percona.com/get/percona-toolkit.rpm

          wget percona.com/get/percona-toolkit.deb

       You can also get individual tools from the latest release:

          wget percona.com/get/TOOL

       Replace "TOOL" with the name of any tool.

AUTHORS

       Baron Schwartz, based on a script by Domas Mituzas (<http://poormansprofiler.org/>)

ABOUT PERCONA TOOLKIT

       This tool is part of Percona Toolkit, a collection of advanced command-line tools for
       MySQL developed by Percona.  Percona Toolkit was forked from two projects in June, 2011:
       Maatkit and Aspersa.  Those projects were created by Baron Schwartz and primarily
       developed by him and Daniel Nichter.  Visit <http://www.percona.com/software/> to learn
       about other free, open-source software from Percona.

COPYRIGHT, LICENSE, AND WARRANTY

       This program is copyright 2011-2018 Percona LLC and/or its affiliates, 2010-2011 Baron
       Schwartz.

       THIS PROGRAM IS PROVIDED "AS IS" AND WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING,
       WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
       PURPOSE.

       This program is free software; you can redistribute it and/or modify it under the terms of
       the GNU General Public License as published by the Free Software Foundation, version 2; OR
       the Perl Artistic License.  On UNIX and similar systems, you can issue `man perlgpl' or
       `man perlartistic' to read these licenses.

       You should have received a copy of the GNU General Public License along with this program;
       if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston,
       MA  02111-1307  USA.

VERSION

       pt-pmp 3.2.1