ID 498574 - [S] Server enters deadlock when it runs out of MySQL connections

Problem summary

Code in the server can deadlock waiting for MySQL connections to be freed when the server runs out of connections in the MySQL connection pool.

Customer reported version

6.3.7-1

Customer reported platform

CentOS 7

Steps to reproduce

1. Set mysql_max_connections to 1
2. Log in to the server

Expected behaviour

The list of shows loads as expected, and you can browse shows, sequences, and revisions as normal.

Actual behaviour

The server hangs.

Workaround

Raise the number of mysql_max_connections in the flix_server config.yml file. The default value is 70. Please remember to raise the max_allowed_connections in your MySQL server config to accommodate the new Flix server setting times the number of Flix servers you have and add a few extra connection (so you can connected to the MySQL server manually for troubleshooting). For example if you have 5 Flix servers please set mysql_max_connections in the Flix config.yml file to 200 and the max_connections in MySQL to 1010.