RowDeck blogNotes on running MySQL and MariaDB in production, from the developer of RowDeck.https://rowdeck.app/enERROR 1040 Too many connections: getting back into a full MySQL serverhttps://rowdeck.app/blog/mysql-too-many-connections/https://rowdeck.app/blog/mysql-too-many-connections/Once max_connections is full, MySQL turns away new clients, you included. The reserved admin slot, the admin port, and finding who holds the slots.Mon, 26 Oct 2026 00:00:00 GMTWhy KILL QUERY didn't release the row lockhttps://rowdeck.app/blog/kill-query-sleeping-transaction/https://rowdeck.app/blog/kill-query-sleeping-transaction/A MySQL thread asleep in an open transaction keeps its row locks, and KILL QUERY can't touch it. Finding that thread, ending it, and stopping the next one.Sun, 25 Oct 2026 00:00:00 GMTOne ALTER TABLE can stop every query on a MySQL tablehttps://rowdeck.app/blog/alter-table-metadata-lock-queue/https://rowdeck.app/blog/alter-table-metadata-lock-queue/A migration waiting for a metadata lock queues each later query on its table. Finding the forgotten transaction behind it and keeping it from coming back.Sat, 24 Oct 2026 00:00:00 GMT