Queries to MyISAM table stuck in "Waiting for table level lock" state

Symptoms

You may see queries stuck in the MySQL process list with the "Waiting for table level lock" state.

Description 

MySQL only uses row-level locking in InnoDB tables. Other storage engines use table-level locks, as documented at:

https://dev.mysql.com/doc/refman/8.0/en/internal-locking.html

Due to this, MyISAM tables with write-heavy workloads can experience high lock contention.

Workaround

The MyISAM tables can be converted to InnoDB tables which support row-level locking. This should be performed by a qualified System or Database Administrator. This can be done with the following commands, replacing DATABASE_NAME and TABLE_NAME as appropriate.

1) Ensure that backups exist for the table prior to converting.

mysqldump DATABASE_NAME TABLE_NAME > TABLE_NAME.sql

2) Convert the table to InnoDB

mysql -e "ALTER TABLE DATABASE_NAME.TABLE_NAME ENGINE=InnoDB"