Description:
I am using the lua script from the mysql-proxy github: https://github.com/cwarden/mysql-proxy/blob/master/examples/tutorial-keepalive.lua
Once mysql-proxy reaches min_idle_connections + 1, every attempted connection after that will alternate between failing and succeeding (almost identical to bug #51954)
Here is an example of the issue:
-----------------------------------------------------
[connect_server] <--------- first client connects fine
[1].connected_clients = 0
[1].idling_connections = 0
[1].type = 1
[1].state = 0
[1] open new connection
[read_query]
authed backend = 0
used db = commandconsole
[connect_server] <--------- second client connects fine
[1].connected_clients = 0
[1].idling_connections = 1
[1].type = 1
[1].state = 1
opening new connection on: 1
[read_query]
authed backend = 0
used db = commandconsole
[connect_server] <--------- third client connects fine
[1].connected_clients = 0
[1].idling_connections = 2
[1].type = 1
[1].state = 1
opening new connection on: 1
[read_query]
authed backend = 0
used db = commandconsole
[connect_server] <--------- fourth client connects fine at first
[1].connected_clients = 0
[1].idling_connections = 3
[1].type = 1
[1].state = 1
using pooled connection from: 1
[disconnect_client] <--------- fourth client disconnects automatically
----------------------------
As you can see in the very last line, it automatically disconnects the client. This is the error on the client side:
ERROR 1047 (08S01): Unknown command
The next time I try to connect it will succeed, but the time after that it will fail again. I have tried the old passwords fix but it does not work.
Thanks.
How to repeat:
mysql-5.5.25
-- connection pool
local min_idle_connections = 2
local max_idle_connections = 6
mysql-proxy --proxy-backend-addresses=awef.example.com:3306 --proxy-address=mysql-proxy-test.example.com:3306 --proxy-lua-script=/root/tutorial-keepalive.lua
Connect to MySQL 4 times.
Suggested fix:
The client shouldn't automatically disconnect if there are idle connections available for use.
