Check mysql-table-locks

Overview

Checks whether a certain percentage of table locks had to wait in MySQL/MariaDB. Logic is taken from MySQLTuner script:mysql_stats(), v1.9.8.

Hints:

  • On RHEL 7+, one way to install the Python MySQL Connector is via pip install pymysql

  • Compared to check_mysql / MySQLTuner this check currently:

    • supports only simple login with username/password (not via SSL/TLS)

    • does not support a connection via socket

Fact Sheet

Check Plugin Download

https://github.com/Linuxfabrik/monitoring-plugins/tree/main/check-plugins/mysql-table-locks

Check Interval Recommendation

Once an hour

Can be called without parameters

Yes

Available for

Python 3, Windows

Requirements

Python module pymysql; User with no privileges, locked down to 127.0.0.1 - for example monitoring@127.0.0.1. Usernames in MySQL/MariaDB are limited to 16 chars in specific versions.

Help

usage: mysql-table-locks [-h] [-V] [--always-ok] [-H HOSTNAME] [-p PASSWORD]
                         [--port PORT] [-u USERNAME]

Checks whether a certain percentage of table locks had to wait in
MySQL/MariaDB.

options:
  -h, --help            show this help message and exit
  -V, --version         show program's version number and exit
  --always-ok           Always returns OK.
  -H HOSTNAME, --hostname HOSTNAME
                        MySQL/MariaDB hostname. Default: 127.0.0.1
  -p PASSWORD, --password PASSWORD
                        Use the indicated password to authenticate the
                        connection. Default:
  --port PORT           MySQL/MariaDB port. Default: 3306
  -u USERNAME, --username USERNAME
                        MySQL/MariaDB username. Default: root

Usage Examples

./mysql-table-locks --hostname localhost --username root --password mypassword

Output:

100% table locks acquired immediately (2.6K immediate / 2.6K locks).

States

  • WARN if less than 95% table locks were completed immediately.

Perfdata / Metrics

Name

Type

Description

mysql_pct_table_locks_immediate

Percentage

Table_locks_immediate / (Table_locks_waited + Table_locks_immediate) * 100

mysql_table_locks_immediate

Continous Counter

Number of table locks which were completed immediately.

mysql_table_locks_waited

Continous Counter

Number of table locks which had to wait. Indicates table lock contention.

Credits, License