Provided by: percona-toolkit_2.2.7-1~dfsg1_all bug

NAME

       pt-deadlock-logger - Log MySQL deadlocks.

SYNOPSIS

       Usage: pt-deadlock-logger [OPTIONS] DSN

       pt-deadlock-logger logs information about MySQL deadlocks on the given DSN.  Information
       is printed to "STDOUT", and it can also be saved to a table by specifying "--dest".  The
       tool runs for forever unless "--run-time" or "--iterations" is specified.

       Print deadlocks on host1:

          pt-deadlock-logger h=host1

       Print deadlocks on host1 once then exit:

          pt-deadlock-logger h=host1 --iterations 1

       Save deadlocks on host1 to percona_schema.deadlocks on host2:

         pt-deadlock-logger h=host1 --dest h=host2,D=percona_schema,t=deadlocks

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-deadlock-logger prints information about MySQL deadlocks by polling and parsing "SHOW
       ENGINE INNODB STATUS".  When a new deadlock occurs, it's printed to "STDOUT" and, if
       specified, saved to "--dest".

       Only new deadlocks are printed.  A fingerprint for each deadlock is created using the
       deadlock's server, ts, and thread values (even if these columns are not specified by
       "--columns").  A deadlock is printed if its fingerprint is different than the last
       deadlock's fingerprint.

       The "--dest" statement uses "INSERT IGNORE" to eliminate duplicate deadlocks, so every
       deadlock is saved for every "--iterations".

OUTPUT

       New deadlocks are printed to "STDOUT", unless "--quiet" is specified.  Errors and warnings
       are printed to "STDERR".

       See also "--columns" and "--tab".

INNODB CAVEATS AND DETAILS

       InnoDB's output is hard to parse and sometimes there's no way to do it right.

       Sometimes not all information (for example, username or IP address) is included in the
       deadlock information.  In this case there's nothing for the tool to put in those columns.
       It may also be the case that the deadlock output is so long (because there were a lot of
       locks) that the whole thing is truncated.

       Though there are usually two transactions involved in a deadlock, there are more locks
       than that; at a minimum, one more lock than transactions is necessary to create a cycle in
       the waits-for graph.  pt-deadlock-logger prints the transactions (always two in the InnoDB
       output, even when there are more transactions in the waits-for graph than that) and fills
       in locks.  It prefers waited-for over held when choosing lock information to output, but
       you can figure out the rest with a moment's thought.  If you see one wait-for and one held
       lock, you're looking at the same lock, so of course you'd prefer to see both wait-for
       locks and get more information.  If the two waited-for locks are not on the same table,
       more than two transactions were involved in the deadlock.

       Finally, keep in mind that, because usernames with spaces are not quoted by InnoDB, the
       tool will generally misreport the second word of these usernames as the hostname.

OPTIONS

       This tool accepts additional command-line arguments.  Refer to the "SYNOPSIS" and usage
       information for details.

       --ask-pass
           Prompt for a password when connecting to MySQL.

       --charset
           short form: -A; type: string

           Default character set.  If the value is utf8, sets Perl's binmode on STDOUT to utf8,
           passes the mysql_enable_utf8 option to DBD::mysql, and runs SET NAMES UTF8 after
           connecting to MySQL.  Any other value sets binmode on STDOUT without the utf8 layer,
           and runs SET NAMES after connecting to MySQL.

       --clear-deadlocks
           type: string

           Use this table to create a small deadlock.  This usually has the effect of clearing
           out a huge deadlock, which otherwise consumes the entire output of "SHOW INNODB
           STATUS".  The table must not exist.  pt-deadlock-logger will create it with the
           following structure:

             CREATE TABLE percona_schema.clear_deadlocks (
               a INT PRIMARY KEY
             ) ENGINE=InnoDB

           After creating the table and causing a small deadlock, the tool will drop the table
           again.

       --columns
           type: Array; default: server, ts, thread, txn_id, txn_time, user, hostname, ip, db,
           tbl, idx, lock_type, lock_mode, wait_hold, victim, query

           The columns are:

           server
               The (source) server on which the deadlock occurred.  This might be useful if
               you're tracking deadlocks on many servers.

           ts  The date and time of the last detected deadlock.

           thread
               The MySQL thread number, which is the same as the connection ID in SHOW FULL
               PROCESSLIST.

           txn_id
               The InnoDB transaction ID, which InnoDB expresses as two unsigned integers.  I
               have multiplied them out to be one number.

           txn_time
               How long the transaction was active when the deadlock happened.

           user
               The connection's database username.

           hostname
               The connection's host.

           ip  The connection's IP address.  If you specify "--numeric-ip", this is converted to
               an unsigned integer.

           db  The database in which the deadlock occurred.

           tbl The table on which the deadlock occurred.

           idx The index on which the deadlock occurred.

           lock_type
               The lock type the transaction held on the lock that caused the deadlock.

           lock_mode
               The lock mode of the lock that caused the deadlock.

           wait_hold
               Whether the transaction was waiting for the lock or holding the lock.  Usually you
               will see the two waited-for locks.

           victim
               Whether the transaction was selected as the deadlock victim and rolled back.

           query
               The query that caused the deadlock.

       --config
           type: Array

           Read this comma-separated list of config files; if specified, this must be the first
           option on the command line.

       --create-dest-table
           Create the table specified by "--dest".

           Normally the "--dest" table is expected to exist already.  This option causes pt-
           deadlock-logger to create the table automatically using the suggested table structure.

       --daemonize
           Fork to the background and detach from the shell.  POSIX operating systems only.

       --database
           short form: -D; type: string

           Connect to this database.

       --defaults-file
           short form: -F; type: string

           Only read mysql options from the given file.  You must give an absolute pathname.

       --dest
           type: DSN

           DSN for where to store deadlocks; specify at least a database (D) and table (t).

           Missing values are filled in with the same values from the source host, so you can
           usually omit most parts of this argument if you're storing deadlocks on the same
           server on which they happen.

           The following table structure is suggested if you want to store all the information
           pt-deadlock-logger can extract about deadlocks:

            CREATE TABLE deadlocks (
              server char(20) NOT NULL,
              ts datetime NOT NULL,
              thread int unsigned NOT NULL,
              txn_id bigint unsigned NOT NULL,
              txn_time smallint unsigned NOT NULL,
              user char(16) NOT NULL,
              hostname char(20) NOT NULL,
              ip char(15) NOT NULL, -- alternatively, ip int unsigned NOT NULL
              db char(64) NOT NULL,
              tbl char(64) NOT NULL,
              idx char(64) NOT NULL,
              lock_type char(16) NOT NULL,
              lock_mode char(1) NOT NULL,
              wait_hold char(1) NOT NULL,
              victim tinyint unsigned NOT NULL,
              query text NOT NULL,
              PRIMARY KEY  (server,ts,thread)
            ) ENGINE=InnoDB

           If you use "--columns", you can omit whichever columns you don't want to store.

       --help
           Show help and exit.

       --host
           short form: -h; type: string

           Connect to host.

       --interval
           type: time; default: 30

           How often to check for deadlocks.  If no "--run-time" is specified, pt-deadlock-logger
           runs forever, checking for deadlocks at every interval.  See also "--run-time".

       --iterations
           type: int

           How many times to check for deadlocks.  By default, this option is undefined which
           means an infinite number of iterations.  The tool always exits for "--run-time",
           regardless of the value specified for this option.  For example, the tool will exit
           after 1 minute with "--run-time 1m --iterations 4 --interval 30" because 4 iterations
           at 30 second intervals would take 2 minutes, longer than the 1 mintue run-time.

       --log
           type: string

           Print all output to this file when daemonized.

       --numeric-ip
           Express IP addresses as integers.

       --password
           short form: -p; type: string

           Password to use when connecting.

       --pid
           type: string

           Create the given PID file.  The tool won't start if the PID file already exists and
           the PID it contains is different than the current PID.  However, if the PID file
           exists and the PID it contains is no longer running, the tool will overwrite the PID
           file with the current PID.  The PID file is removed automatically when the tool exits.

       --port
           short form: -P; type: int

           Port number to use for connection.

       --quiet
           Do not deadlocks; only print errors and warnings to "STDERR".

       --run-time
           type: time

           How long to run before exiting.  By default pt-deadlock-logger runs forever, checking
           for deadlocks every "--interval" seconds.

       --set-vars
           type: Array

           Set the MySQL variables in this comma-separated list of "variable=value" pairs.

           By default, the tool sets:

              wait_timeout=10000

           Variables specified on the command line override these defaults.  For example,
           specifying "--set-vars wait_timeout=500" overrides the defaultvalue of 10000.

           The tool prints a warning and continues if a variable cannot be set.

       --socket
           short form: -S; type: string

           Socket file to use for connection.

       --tab
           Use tabs to separate columns instead of spaces.

       --user
           short form: -u; type: string

           User for login if not current user.

       --version
           Show version and exit.

       --[no]version-check
           default: yes

           Check for the latest version of Percona Toolkit, MySQL, and other programs.

           This is a standard "check for updates automatically" feature, with two additional
           features.  First, the tool checks the version of other programs on the local system in
           addition to its own version.  For example, it checks the version of every MySQL server
           it connects to, Perl, and the Perl module DBD::mysql.  Second, it checks for and warns
           about versions with known problems.  For example, MySQL 5.5.25 had a critical bug and
           was re-released as 5.5.25a.

           Any updates or known problems are printed to STDOUT before the tool's normal output.
           This feature should never interfere with the normal operation of the tool.

           For more information, visit <https://www.percona.com/version-check>.

DSN OPTIONS

       These DSN options are used to create a DSN.  Each option is given like "option=value".
       The options are case-sensitive, so P and p are not the same option.  There cannot be
       whitespace before or after the "=" and if the value contains whitespace it must be quoted.
       DSN options are comma-separated.  See the percona-toolkit manpage for full details.

       •   A

           dsn: charset; copy: yes

           Default character set.

       •   D

           dsn: database; copy: yes

           Default database.

       •   F

           dsn: mysql_read_default_file; copy: yes

           Only read default options from the given file

       •   h

           dsn: host; copy: yes

           Connect to host.

       •   p

           dsn: password; copy: yes

           Password to use when connecting.

       •   P

           dsn: port; copy: yes

           Port number to use for connection.

       •   S

           dsn: mysql_socket; copy: yes

           Socket file to use for connection.

       •   t

           Table in which to store deadlock information.

       •   u

           dsn: user; copy: yes

           User for login if not current user.

ENVIRONMENT

       The environment variable "PTDEBUG" enables verbose debugging output to STDERR.  To enable
       debugging and capture all output to a file, run the tool like:

          PTDEBUG=1 pt-deadlock-logger ... > FILE 2>&1

       Be careful: debugging output is voluminous and can generate several megabytes of output.

SYSTEM REQUIREMENTS

       You need Perl, DBI, DBD::mysql, and some core packages that ought to be installed in any
       reasonably new version of Perl.

BUGS

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

       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 and Daniel Nichter

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 2011-2014 Percona LLC and/or its affiliates, 2007-2011 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-deadlock-logger 2.2.7