MySQL giving “read ECONNRESET” error after idle time on node.js server

I reached out to the node-mysql folks on their Github page and got some firm answers.

1. MySQL does indeed prune idle connections. There’s a MySQL variable “wait_timeout” that sets the number of second before timeout and the default is 8 hours. We can set the default to be much larger than that. Use show variables like 'wait_timeout'; to view your timeout setting and set wait_timeout=28800; to change it.

2. According to this issue, node-mysql doesn’t prune pool connections after these sorts of disconnections. The module developers recommended using a heartbeat to keep the connection alive such as calling SELECT 1; on an interval. They also recommended using the node-pool module and its idleTimeoutMillis option to automatically prune idle connections.