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MySQLTuner is a script written in Perl that will assist you with your MySQL configuration and make recommendations for increased performance and stability.


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Project Status Test Status Average time to resolve an issue Percentage of open issues GPL License

MySQLTuner is a script written in Perl that allows you to review a MySQL installation quickly and make adjustments to increase performance and stability. The current configuration variables and status data is retrieved and presented in a brief format along with some basic performance suggestions.

MySQLTuner supports ~300 indicators for MySQL/MariaDB/Percona Server in this latest version.

MySQLTuner is actively maintained supporting many configurations such as Galera Cluster, TokuDB, Performance schema, Linux OS metrics, InnoDB, MyISAM, Aria, ...

You can find more details on these indicators here: Indicators description.


MySQLTuner needs you

MySQLTuner needs contributors for documentation, code and feedback:

Anurag's GitHub stats

Stargazers over time

Stargazers over time


Test result are available here:

  • MySQL 8.0, 8.2, 8.3 (full support)

  • Percona Server 8.0, 8.2, 8.3 (full support)

  • MariaDB 10.4, 10.5, 10.6, 10.11, 11.0, 11.1, 11.2 (full support)

  • Galera replication (full support)

  • Percona XtraDB cluster (full support)

  • Mysql Replications (partial support, no test environment)

  • MySQL 8.1 (not supported, deprecated version)

  • Percona Server 5.7 (not supported, deprecated version)

  • MySQL 5.7 (not supported, deprecated version)

  • MySQL 5.6 and earlier (not supported, deprecated version)

  • Percona Server 5.6 (not supported, deprecated version)

  • MariaDB 10.7, 10.8, 10.9, 10.10 (not supported, deprecated version)

  • MariaDB 10.3 and earlier (not supported, deprecated version)

  • MariaDB 5.5 (not supported, deprecated version)

Windows Support is partial


  • Cloud based is not supported at this time (Help wanted! GCP, AWS, Azure support requested)

Unsupported storage engines: PRs welcome

  • NDB is not supported feel free to create a Pull Request
  • Archive
  • Spider
  • ColummStore
  • Connect

Unmaintenained staff from MySQL or MariaDB:

  • MyISAM is too old and no longer active

  • RockDB is not maintained anymore

  • TokuDB is not maintained anymore

  • XtraDB is not maintained anymore

  • CVE vulnerabilities detection support from


  • Perl 5.6 or later (with perl-doc package)
  • Unix/Linux based operating system (tested on Linux, BSD variants, and Solaris variants)
  • Unrestricted read access to the MySQL server OS root access recommended for MySQL < 5.1


It is important for you to fully understand each change you make to a MySQL database server. If you don't understand portions of the script's output, or if you don't understand the recommendations, you should consult a knowledgeable DBA or system administrator that you trust. Always test your changes on staging environments, and always keep in mind that improvements in one area can adversely affect MySQL in other areas.

It's also important to wait at least 24 hours of uptime to get accurate results. In fact, running mysqltuner on a fresh restarted server is completely useless.

Also review the FAQ section below.

Security recommendations

Hi directadmin user! We detected that you run mysqltuner with da_admin's credentials taken from /usr/local/directadmin/conf/my.cnf, which might bring to a password discovery! Read link for more details Issue #289.

What is MySQLTuner checking exactly ?

All checks done by MySQLTuner are documented in MySQLTuner Internals documentation.


Choose one of these methods:

  1. Script direct download (the simplest and shortest method):
wget -O
wget -O basic_passwords.txt
wget -O vulnerabilities.csv
  1. You can download the entire repository by using git clone or git clone --depth 1 -b master followed by the cloning URL above.

Optional Sysschema installation for MySQL 5.6

Sysschema is installed by default under MySQL 5.7 and MySQL 8 from Oracle. By default, on MySQL 5.6/5.7/8, performance schema is enabled by default. For previous MySQL 5.6 version, you can follow this command to create a new database sys containing very useful view on Performance schema:

Sysschema for MySQL old version

curl "" >
# check zip file
unzip -l
cd mysql-sys-master
mysql -uroot -p < sys_56.sql

Sysschema for MariaDB old version

curl "" >
# check zip file
unzip -l
cd mariadb-sys-master
mysql -u root -p < ./sys_10.sql

Performance schema setup

By default, performance_schema is enabled and sysschema is installed on latest version.

By default, on MariaDB, performance schema is disabled by default (MariaDB<10.6).

Consider activating performance schema across your my.cnf configuration file:

performance_schema = on
performance-schema-consumer-events-statements-history-long = ON
performance-schema-consumer-events-statements-history = ON
performance-schema-consumer-events-statements-current = ON

Sysschema installation for MariaDB < 10.6

Sysschema is not installed by default under MariaDB prior to 10.6 MariaDB sys

You can follow this command to create a new database sys containing a useful view on Performance schema:

curl "" >
# check zip file
unzip -l
cd mariadb-sys-master/
mysql -u root -p < ./sys_10.sql

Errors & solutions for performance schema installation

ERROR 1054 (42S22) at line 78 in file: './views/p_s/metrics_56.sql': Unknown column 'STATUS' in 'field list'

This error can be safely ignored Consider using a recent MySQL/MariaDB version to avoid this kind of issue during sysschema installation

In recent versions, sysschema is installed and integrated by default as sys schema (SHOW DATABASES)

ERROR at line 21: Failed to open file './tables/sys_config_data_10.sql -- ported', error: 2 Have a look at #452 solution given by @ericx

Fixing sysctl configuration (/etc/sysctl.conf)

-- It is a system wide setting and not a database setting: Linux FS Kernel settings

You can check its values via:

$ cat /proc/sys/fs/aio-*

For example, to set the aio-max-nr value, add the following line to the /etc/sysctl.conf file:

fs.aio-max-nr = 1048576

To activate the new setting:

$ sysctl -p /etc/sysctl.conf

Specific usage

Usage: Minimal usage locally

perl --host

Of course, you can add the execute bit (chmod +x so you can execute it without calling Perl directly.

Usage: Minimal usage remotely

In previous version, --forcemem shoud be set manually, in order to be able to run an MySQLTuner analysis

Since 2.1.10, memory and swap are defined to 1Gb by default.

If you want a more accurate value according to your remote server, feel free to setup --forcemem and --forceswap to real RAM value

perl --host targetDNS_IP --user admin_user --pass admin_password

Usage: Enable maximum output information around MySQL/MariaDb without debugging

perl --verbose
perl --buffers --dbstat --idxstat --sysstat --pfstat --tbstat

Usage: Enable CVE vulnerabilities check for your MariaDB or MySQL version

perl --cvefile=vulnerabilities.csv

Usage: Write your result in a file with information displayed

perl --outputfile /tmp/result_mysqltuner.txt

Usage: Write your result in a file without outputting information

perl --silent --outputfile /tmp/result_mysqltuner.txt

Usage: Using template model to customize your reporting file based on Text::Template syntax.

perl --silent --reportfile /tmp/result_mysqltuner.txt --template=/tmp/mymodel.tmpl

Important: Text::Template module is mandatory for --reportfile and/or --template options, because this module is needed to generate appropriate output based on a text template.

Usage: Dumping all information_schema and sysschema views as csv file into results subdirectory

perl --verbose --dumpdir=./result

Usage: Enable debugging information

perl --debug

Usage: Update MySQLTuner and data files (password and cve) if needed

perl --checkversion --updateversion

HTML reports based on Python Jinja2

HTML generation is based on Python/Jinja2

HTML generation Procedure

  • Generate report using JSON format (--json)
  • Generate HTML report using j2 python tools

Jinja2 Templates are located under templates sub directory

A basic example is called basic.html.j2

Installation Python j2

python -mvenv j2
source ./j2/bin/activate
(j2) pip install j2

Using Html report generation

perl --verbose --json > reports.json
cat reports.json  j2 -f json MySQLTuner-perl/templates/basic.html.j2 > variables.html


perl --verbose --json | j2 -f json MySQLTuner-perl/templates/basic.html.j2 > variables.html

HTML reports based on AHA

HTML generation is based on AHA

HTML generation Procedure

  • Generate report using standard text reports
  • Generate HTML report using aha

Installation Aha

Follow instructions from Github repo

GitHub AHA main repository

Using AHA Html report generation

perl --verbose --color > reports.txt
aha --black --title "MySQLTuner" -f "reports.txt" > "reports.html"


perl --verbose --color | aha --black --title "MySQLTuner" > reports.html


Question: What are the prerequisites for running MySQL tuner ?

Before running MySQL tuner, you should have the following:

  • A MySQL server installation
  • Perl installed on your system
  • Administrative access to your MySQL server

Question: Can MySQL tuner make changes to my configuration automatically ?

No., MySQL tuner only provides recommendations. It does not make any changes to your configuration files automatically. It is up to the user to review the suggestions and implement them as needed.

Question: How often should I run MySQL tuner ?

It is recommended to run MySQL tuner periodically, especially after significant changes to your MySQL server or its workload.

For optimal results, run the script after your server has been running for at least 24 hours to gather sufficient performance data.

Question: How do I interpret the results from MySQL tuner ?

MySQL tuner provides output in the form of suggestions and warnings.

Review each recommendation and consider implementing the changes in your MySQL configuration file (usually 'my.cnf' or 'my.ini').

Be cautious when making changes and always backup your configuration file before making any modifications.

Question: Can MySQL tuner cause harm to my database or server ?

While MySQL tuner itself will not make any changes to your server, blindly implementing its recommendations without understanding the impact can cause issues.

Always ensure you understand the implications of each suggestion before applying it to your server.

Question: Can I use MySQL tuner for optimizing other database systems like PostgreSQL or SQL Server ?

MySQL tuner is specifically designed for MySQL servers. To optimize other database systems, you would need to use tools designed for those systems, such as pgTune for PostgreSQL or SQL Server's built-in performance tools.

Question: Does MySQL tuner support MariaDB and Percona Server ?

Yes, MySQL tuner supports MariaDB and Percona Server since they are derivatives of MySQL and share a similar architecture. The script can analyze and provide recommendations for these systems as well.

Question: What should I do if I need help with MySQL tuner or have questions about the recommendations ?

If you need help with MySQL tuner or have questions about the recommendations provided by the script, you can consult the MySQL tuner documentation, seek advice from online forums, or consult a MySQL expert.

Be cautious when implementing changes to ensure the stability and performance of your server.

Question: Will MySQLTuner fix my slow MySQL server ?

No. MySQLTuner is a read only script. It won't write to any configuration files, change the status of any daemons. It will give you an overview of your server's performance and make some basic recommendations for improvements that you can make after it completes.

Question: Can I fire my DBA now?

MySQLTuner will not replace your DBA in any form or fashion.

If your DBA constantly takes your parking spot and steals your lunch from the fridge, then you may want to consider it - but that's your call.

Question: Why does MySQLTuner keep asking me the login credentials for MySQL over and over?

The script will try its best to log in via any means possible. It will check for ~/.my.cnf files, Plesk password files, and empty password root logins. If none of those are available, then you'll be prompted for a password. If you'd like the script to run in an automated fashion without user intervention, then create a .my.cnf file in your home directory which contains:


Once you create it, make sure it's owned by your user and the mode on the file is 0600. This should prevent the prying eyes from getting your database login credentials under normal conditions.

Question: Is there another way to secure credentials on latest MySQL and MariaDB distributions ?

You could use mysql_config_editor utilities.

	$ mysql_config_editor set --login-path=client --user=someusername --password --host=localhost
	Enter password: ********

After which, ~/.mylogin.cnf will be created with the appropriate access.

To get information about stored credentials, use the following command:

$mysql_config_editor print
user = someusername
password = *****
host = localhost

Question: What's minimum privileges needed by a specific mysqltuner user in database ?

 ON *.*
 TO 'mysqltuner'@'localhost' identified by pwd1234;

Question: It's not working on my OS! What gives?!

These kinds of things are bound to happen. Here are the details I need from you to investigate the issue:

  • OS and OS version
  • Architecture (x86, x86_64, IA64, Commodore 64)
  • Exact MySQL version
  • Where you obtained your MySQL version (OS package, source, etc)
  • The full text of the error
  • A copy of SHOW VARIABLES and SHOW GLOBAL STATUS output (if possible)

Question: How to perform CVE vulnerability checks?

  • Download vulnerabilities.csv from this repository.
  • use option --cvefile to perform CVE checks

Question: How to use mysqltuner from a remote host? Thanks to @rolandomysqldba

  • You will still have to connect like a mysql client:

Connection and Authentication

--host <hostname> Connect to a remote host to perform tests (default: localhost)
--socket <socket> Use a different socket for a local connection
--port <port>     Port to use for connection (default: 3306)
--user <username> Username to use for authentication
--pass <password> Password to use for authentication
--defaults-file <path> defaults file for credentials

Since you are using a remote host, use parameters to supply values from the OS

--forcemem <size>  Amount of RAM installed in megabytes
--forceswap <size> Amount of swap memory configured in megabytes
  • You may have to contact your remote SysAdmin to ask how much RAM and swap you have

If the database has too many tables, or very large table, use this:

--skipsize           Don't enumerate tables and their types/sizes (default: on)
                     (Recommended for servers with many tables)

Question: Can I install this project using homebrew on Apple Macintosh?

Yes! brew install mysqltuner can be used to install this application using homebrew on Apple Macintosh.

MySQLTuner and Vagrant

MySQLTuner contains following Vagrant configurations:

  • Fedora Core 30 / Docker

Vagrant File is stored in Vagrant subdirectory.

  • Follow following step after vagrant installation: $ vagrant up

MySQLTuner contains a Vagrant configurations for test purpose and development

setup test environments

$ sh build/

$ source build/bashrc
$ mysql_percona80 sakila
sakila> ...

$ docker images
mariadb                  10.1                fc612450e1f1        12 days ago         352MB
mariadb                  10.2                027b7c57b8c6        12 days ago         340MB
mariadb                  10.3                47dff68107c4        12 days ago         343MB
mariadb                  10.4                92495405fc36        12 days ago         356MB
mysql                    5.6                 95e0fc47b096        2 weeks ago         257MB
mysql                    5.7                 383867b75fd2        2 weeks ago         373MB
mysql                    8.0                 b8fd9553f1f0        2 weeks ago         445MB
percona/percona-server   5.7                 ddd245ed3496        5 weeks ago         585MB
percona/percona-server   5.6                 ed0a36e0cf1b        6 weeks ago         421MB
percona/percona-server   8.0                 390ae97d57c6        6 weeks ago         697MB
mariadb                  5.5                 c7bf316a4325        4 months ago        352MB
mariadb                  10.0                d1bde56970c6        4 months ago        353MB
mysql                    5.5                 d404d78aa797        4 months ago        205MB

$ docker ps
CONTAINER ID        IMAGE                        COMMAND                  CREATED             STATUS              PORTS                               NAMES
da2be9b050c9        mariadb:5.5                  "docker-entrypoint.s…"   7 hours ago         Up 7 hours>3306/tcp              mariadb55
5deca25d5ac8        mariadb:10.0                 "docker-entrypoint.s…"   7 hours ago         Up 7 hours>3306/tcp              mariadb100
73aaeb37e2c2        mariadb:10.1                 "docker-entrypoint.s…"   7 hours ago         Up 7 hours>3306/tcp              mariadb101
72ffa77e01ec        mariadb:10.2                 "docker-entrypoint.s…"   7 hours ago         Up 7 hours>3306/tcp              mariadb102
f5996f2041df        mariadb:10.3                 "docker-entrypoint.s…"   7 hours ago         Up 7 hours>3306/tcp              mariadb103
4890c52372bb        mariadb:10.4                 "docker-entrypoint.s…"   7 hours ago         Up 7 hours>3306/tcp              mariadb104
6b9dc078e921        percona/percona-server:5.6   "/docker-entrypoint.…"   7 hours ago         Up 7 hours>3306/tcp              percona56
3a4c7c826d4c        percona/percona-server:5.7   "/docker-entrypoint.…"   7 hours ago         Up 7 hours>3306/tcp              percona57
3dda408c91b0        percona/percona-server:8.0   "/docker-entrypoint.…"   7 hours ago         Up 7 hours          33060/tcp,>3306/tcp   percona80
600a4e7e9dcd        mysql:5.5                    "docker-entrypoint.s…"   7 hours ago         Up 7 hours>3306/tcp              mysql55
4bbe54342e5d        mysql:5.6                    "docker-entrypoint.s…"   7 hours ago         Up 7 hours>3306/tcp              mysql56
a49783249a11        mysql:5.7                    "docker-entrypoint.s…"   7 hours ago         Up 7 hours          33060/tcp,>3306/tcp   mysql57
d985820667c2        mysql:8.0                    "docker-entrypoint.s…"   7 hours ago         Up 7 hours>3306/tcp, 33060/tcp   mysql 8    0

Contributions welcome !

How to contribute using Pull Request ? Follow this guide : Pull request creation

Simple steps to create a pull request:

  • Fork this Github project
  • Clone it to your local system
  • Make a new branch
  • Make your changes
  • Push it back to your repo
  • Click the Compare & pull request button
  • Click Create pull request to open a new pull request