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Check mysql-system

Overview

Checks system requirements and kernel settings specifically for MySQL/MariaDB. Logic is taken from MySQLTuner script:get_kernel_info(), v1.9.8.

Unlike MySQLTuner, this plugin does not check if all processes other than MySQL/MariaDB use more than 15% of the total system memory. One reason for this is that you may want or need to run a small DB server on an application server and have it well tuned for that use case. Another reason is that if you are running MySQL/MariaDB on an application server with a lot of RAM, the DB may not need or require 85% RAM.

Hints:

  • See additional notes for all mysql monitoring plugins
  • Does not need access to MySQL/MariaDB itself.
  • Must be running locally on the MySQL/MariaDB server to be able to check the system requirements.
  • On Windows there are no kernel settings that can be checked.

Fact Sheet

Fact Value
Check Plugin Download https://github.com/Linuxfabrik/monitoring-plugins/tree/main/check-plugins/mysql-system
Check Interval Recommendation Every 5 minutes
Can be called without parameters Yes
Compiled for Windows No
3rd Party Python modules psutil

Help

usage: mysql-system [-h] [-V] [--always-ok]
                    [--maxportsallowed MAXPORTSALLOWED]

Checks system requirements and kernel settings specifically for 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.
  --maxportsallowed MAXPORTSALLOWED
                        Number of ports opened allowed on this host. Default:
                        0 (check disabled)

Usage Examples

./mysql-system --maxportsallowed 15

Output:

There are too many listening ports: 56 opened > 15 allowed (consider dedicating a server for your database installation with less services running on). vm.swappiness is 60, should be <= 10 (use `echo 10 > /proc/sys/vm/swappiness`). sunrpc.tcp_slot_table_entries is 2, should be > 100 (use `echo 128 > /proc/sys/sunrpc/tcp_slot_table_entries`).

States

  • WARN if there are too many listening ports.
  • WARN if any of the checked Linux Kernel parameters is not in the optimal range.
  • OK in all other cases.

Perfdata / Metrics

Name Type Description
mysql_kernel_fs.aio-max-nr Number Defines the maximum number of asynchronous I/O operations the system can handle on the server.
mysql_kernel_sunrpc.tcp_slot_table_entries Number Sets the number of (TCP) RPC entries to pre-allocate for in-flight RPC requests (essentially the minimum).
mysql_kernel_vm.swappiness Percentage Changes the balance between swapping out runtime memory, as opposed to dropping pages from the system page cache.
mysql_opened_ports Number Number of opened ports.

Credits, License