How to handle slow query logging on MariaDB
Sometimes once you have eliminated all bottlenecks, e.g. NVME and RAM and vCPUs, then all that is left is to check the database. I like
Databases
Isolating disk write performance problems on heavy loaded shared hosting WordPress servers
Background On a heavy loaded WordPress server you might experience the following when looking at iotop. Heavy writes. Additional graphing of the disk’s writes might
MariaDB suspicious Access denied during `debian-start` and then FATAL ERROR: Upgrade failed
On a seemingly working server you may encounter the following checking out the mysql status: Jun 15 10:32:33 host systemd[1]: Starting MariaDB 10.3.39 database server…
Problems with MySQL table optimisation
Example: mysql> optimize table wp_actionscheduler_actions; +——————————————-+———-+———-+——————————————————————-+ | Table
Massive amounts of disk space consumed by MySQL and Mariadb binlog files
Background You might find on a MySQL 8.x or MariaDB 10.4 server that suddenly disk space just evaporates. After using ncdu you see the problem
How to use ‘SHOW PROCESSLIST’ and ‘SHOW FULL PROCESSLUIST’ using MySQL on the command line
Update 28 October 2024 Full processlist isn’t very useful. Instead, just use show processlist. However, if you’re doing performance tuning for a WHM server, check
What defines small medium large and huge on a Virtualmin MySQL installation?
Background When installing Virtualmin, the system will prompt for small, medium, large and huge. The question is how are these parameters defined? By examining the
MySQL Invalid default value for XXX datetime based field
Working servers suddenly start giving the error below when restoring a MySQL database that contains datetime fields with 0000-00-00 defaults: user@server:/tmp# mysql -uuser -ppassword database_name
Beginning MongoDB
MongoDB is a weird little database but seems really popular and works nicely with low overhead Javascript applications. This article highlights a few key pointers
Whilst restoring a MariaDB Backup from one Virtualmin server to another, MySQL create and grant errors
Background On a legacy server with an older version of MariaDB, restoring to a newer Virtualmin server that run MySQL 8 might be problematic. The