Cloud image needs swap
To add a swap file:
If your Hudson is really busy and it launches a lot of processes, in theory you could be temporarily running more than 2 instances of your application server.
There are many ways to check the usage of swap space, but I usually use the “top” command, which is available on most Unix systems.
This is a Unix-specific issue, as Windows launches child processes without forking.
If you know how to do this for OSes not listed here, please add it