Horrible lag with 3 simultaneous players on Ashlands

[DurvalMenezes]

Per subject.

Both the server where the container is running, and the network between the players and the server, are perfectly alright: vmstat 3 on the server during the lag episodes shows it has over 4GB memory free, no swap activity, and is over 95% idle; ping -s 1500 shows zero packet losses, <100ms RTT and <20ms jitter, but nonetheless all the players see lag on the order of many seconds, causing effects like enemies 'teleporting' from one spot to another, hits failing to register, enemies still showing on the display for many seconds after they had already been killed, etc

When one of the player quits, the other two start to see almost no lag, so I think it may be related to the number of players connected.

Is there a way to optimize the container for better performance with more players, and/or better diagnose whatever is causing this issue?