NAME¶
pt-ioprofile - Watch process IO and print a table of file and I/O activity.
SYNOPSIS¶
Usage: pt-ioprofile [OPTIONS] [FILE]
pt-ioprofile does two things: 1) get lsof+strace for -s seconds, 2) aggregate
the result. If you specify a FILE, then step 1) is not performed.
RISKS¶
WARNING: pt-ioprofile freezes the server and may crash the process, or
make it perform badly after detaching, or leave it in a sleeping state! 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
pt-ioprofile should be considered an intrusive tool, and should not be used
on production servers unless you understand and accept the risks.
DESCRIPTION¶
pt-ioprofile uses "strace" and "lsof" to watch a process's
IO and print out a table of files and I/O activity. By default, it watches the
mysqld process for 30 seconds. The output is like:
Tue Dec 27 15:33:57 PST 2011
Tracing process ID 1833
total read write lseek ftruncate filename
0.000150 0.000029 0.000068 0.000038 0.000015 /tmp/ibBE5opS
You probably need to run this tool as root.
pt-ioprofile works by attaching "strace" to the process using
"ptrace()", which will make it run very slowly until
"strace" detaches. In addition to freezing the server, there is some
risk of the process crashing or performing badly after "strace"
detaches from it, or of "strace" not detaching cleanly and leaving
the process in a sleeping state. As a result, this should be considered an
intrusive tool, and should not be used on production servers unless you are
comfortable with that.
OPTIONS¶
- --aggregate
- short form: -a; type: string; default: sum
The aggregate function, either "sum" or "avg".
If sum, then each cell will contain the sum of the values in it. If avg,
then each cell will contain the average of the values in it.
- --cell
- short form: -c; type: string; default: times
The cell contents.
Valid values are:
VALUE CELLS CONTAIN
===== =======================
count Count of I/O operations
sizes Sizes of I/O operations
times I/O operation timing
- --group-by
- short form: -g; type: string; default: filename
The group-by item.
Valid values are:
VALUE GROUPING
===== ======================================
all Summarize into a single line of output
filename One line of output per filename
pid One line of output per process ID
- --help
- Print help and exit.
- --profile-pid
- short form: -p; type: int
The PID to profile, overrides "--profile-process".
- --profile-process
- short form: -b; type: string; default: mysqld
The process name to profile.
- --run-time
- type: int; default: 30
How long to profile.
- --save-samples
- type: string
Filename to save samples in; these can be used for later analysis.
- --version
- Print the tool's version and exit.
ENVIRONMENT¶
This tool does not use any environment variables.
SYSTEM REQUIREMENTS¶
This tool requires the Bourne shell (
/bin/sh).
BUGS¶
For a list of known bugs, see <
http://www.percona.com/bugs/pt-ioprofile>.
Please report bugs at <
https://bugs.launchpad.net/percona-toolkit>.
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
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 2011-2014 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-ioprofile 2.2.11