# Optimized my.cnf configuration for MySQL/MariaSQL
#
# by Fotis Evangelou, developer of Engintron (engintron.com)
#
# ~ Updated January 2020 ~
#
#
# The settings provided below are a starting point for a 2GB - 4GB RAM server with 2-4 CPU cores.
# If you have different resources available you should adjust accordingly to save CPU, RAM & disk I/O usage.
#
# The settings marked with a specific comment or the word "UPD" (after the value)
# should be adjusted for your system by using database diagnostics tools like:
#
# https://github.com/major/MySQLTuner-perl
# or
# https://github.com/RootService/tuning-primer (supports MySQL up to v5.7)
#
# Run either of these scripts before optimizing your database, at least 1 hr after the optimization & finally
# at least once a day for 3 days (without restarting the database) to see how your server performs and if you need
# to re-adjust anything. The more MySQL/MariaDB runs without restarting, the more usage data it gathers, so these
# diagnostics scripts will report in mode detail how MySQL/MariaDB performs.
#
#
# IMPORTANT NOTE: If there is NO comment after a setting value, then 99,9% of the times you won't need to adjust it.
#
#
# --- THINGS TO DO AFTER YOU UPDATE MY.CNF - TROUBLESHOOTING ---
#
# If any terminal commands are mentioned, make sure you execute them as "root" user.
#
# If MySQL or MariaDB cannot start (or restart), then perform the following actions.
#
# 1. If the server had the stock database configuration and you added or updated any
# "innodb_log_*" settings (as suggested below), then execute these commands ONLY
# the first time you apply this configuration:
#
# $ rm -rvf /var/lib/mysql/ib_logfile*
# $ chown -R mysql:mysql /var/lib/mysql
# $ service mysql restart
#
# or use the shorthand command:
# $ rm -rvf /var/lib/mysql/ib_logfile*; chown -R mysql:mysql /var/lib/mysql; service mysql restart
#
# 2. If the setting "bind-address" is not commented out, then make sure the file /etc/hosts is
# properly configured. A good example of a "clean" /etc/hosts file is something like this:
#
# 127.0.0.1 localhost localhost.localdomain localhost4 localhost4.localdomain4
# ::1 localhost localhost.localdomain localhost6 localhost6.localdomain6
# 1.2.3.4 hostname.domain.tld hostname # <-- Replace accordingly!
#
# Finally restart the database service:
#
# $ service mysql restart
#
# 3. If the database service cannot restart even after the first 2 steps, make sure the database data folder
# (common for either MySQL or MariaDB) "/var/lib/mysql" is owned by the "mysql" user AND group.
# Additionally, the folder itself can have 0751 or 0755 file permissions. To fix it, simply do this:
# $ chown -R mysql:mysql /var/lib/mysql
# $ chmod 0755 /var/lib/mysql
#
# Finally restart the database service:
#
# $ service mysql restart
#
#
# ~ FIN ~


[mysql]
port = 3306
socket = /var/run/mysqld/mysqld.sock

[mysqld]
# Required Settings
basedir = /usr
bind_address = 127.0.0.1 # Change to 0.0.0.0 to allow remote connections
datadir = /var/lib/mysql
max_allowed_packet = 256M
max_connect_errors = 1000000
pid_file = /var/run/mysqld/mysqld.pid
port = 3306
skip_external_locking
skip_name_resolve
socket = /var/run/mysqld/mysqld.sock

# Enable for b/c with databases created in older MySQL/MariaDB versions (e.g. when using null dates)
#sql_mode = ERROR_FOR_DIVISION_BY_ZERO,NO_AUTO_CREATE_USER,NO_ ENGINE_SUBSTITUTION,ONLY_FULL_GROUP_BY,STRICT_TRAN S_TABLES

tmpdir = /tmp
user = mysql

# InnoDB Settings
default_storage_engine = InnoDB
innodb_buffer_pool_instances = 2 # Use 1 instance per 1GB of InnoDB pool size
innodb_buffer_pool_size = 2G # Use up to 70-80% of RAM
innodb_file_per_table = 1
innodb_flush_log_at_trx_commit = 0
innodb_flush_method = O_DIRECT
innodb_log_buffer_size = 16M
innodb_log_file_size = 512M
innodb_stats_on_metadata = 0

#innodb_temp_data_file_path = ibtmp1:64M:autoextend:max:20G # Control the maximum size for the ibtmp1 file
#innodb_thread_concurrency = 4 # Optional: Set to the number of CPUs on your system (minus 1 or 2) to better
# contain CPU usage. E.g. if your system has 8 CPUs, try 6 or 7 and check
# the overall load produced by MySQL/MariaDB.
innodb_read_io_threads = 64
innodb_write_io_threads = 64

# MyISAM Settings
query_cache_limit = 4M # UPD - Option supported by MariaDB & up to MySQL 5.7, remove this line on MySQL 8.x
query_cache_size = 64M # UPD - Option supported by MariaDB & up to MySQL 5.7, remove this line on MySQL 8.x
query_cache_type = 1 # Option supported by MariaDB & up to MySQL 5.7, remove this line on MySQL 8.x

key_buffer_size = 32M # UPD

low_priority_updates = 1
concurrent_insert = 2

# Connection Settings
max_connections = 100 # UPD

back_log = 512
thread_cache_size = 100
thread_stack = 192K

interactive_timeout = 180
wait_timeout = 180

# For MySQL 5.7+ only (disabled by default)
#max_execution_time = 30000 # Set a timeout limit for SELECT statements (value in milliseconds).
# This option may be useful to address aggressive crawling on large sites,
# but it can also cause issues (e.g. with backups). So use with extreme caution and test!
# More info at: https://dev.mysql.com/doc/refman/5.7...execution_time

# For MariaDB 10.1.1+ only (disabled by default)
#max_statement_time = 30 # The equivalent of "max_execution_time" in MySQL 5.7+ (set above)
# The variable is of type double, thus you can use subsecond timeout.
# For example you can use value 0.01 for 10 milliseconds timeout.
# More info at: https://mariadb.com/kb/en/aborting-statements/

# Buffer Settings
join_buffer_size = 4M # UPD
read_buffer_size = 3M # UPD
read_rnd_buffer_size = 4M # UPD
sort_buffer_size = 4M # UPD

# Table Settings
# In systemd managed systems like Ubuntu 16.04+ or CentOS 7+, you need to perform an extra action for table_open_cache & open_files_limit
# to be overriden (also see comment next to open_files_limit).
# E.g. for MySQL 5.7, please check: https://dev.mysql.com/doc/refman/5.7...g-systemd.html
# and for MariaDB check: https://mariadb.com/kb/en/library/systemd/
table_definition_cache = 40000 # UPD
table_open_cache = 40000 # UPD
open_files_limit = 60000 # UPD - This can be 2x to 3x the table_open_cache value or match the system's
# open files limit usually set in /etc/sysctl.conf or /etc/security/limits.conf
# In systemd managed systems this limit must also be set in:
# /etc/systemd/system/mysqld.service.d/override.conf (for MySQL 5.7+) and
# /etc/systemd/system/mariadb.service.d/override.conf (for MariaDB)

max_heap_table_size = 128M
tmp_table_size = 128M

# Search Settings
ft_min_word_len = 3 # Minimum length of words to be indexed for search results

# Logging
log_error = /var/lib/mysql/mysql_error.log
log_queries_not_using_indexes = 1
long_query_time = 5
slow_query_log = 0 # Disabled for production
slow_query_log_file = /var/lib/mysql/mysql_slow.log

[mysqldump]
# Variable reference
# For MySQL 5.7: https://dev.mysql.com/doc/refman/5.7/en/mysqldump.html
# For MariaDB: https://mariadb.com/kb/en/library/mysqldump/
quick
quote_names
max_allowed_packet = 64M


See more:
https://gist.github.com/fevangelou/fb72f36bbe333e059b66