I initially tested Moses on a small virtual machine with only 2 GB RAM and 2 cores. I was able to train the system in less than 2 hours, but when I tried to translate a sentence, the decoder would crash.

...Loading table into memory...Killed

I eventually discovered (by running top simultaneously in another shell window) that the error was just a lack of memory. Once I switched to a larger machine (8 GB RAM), the error went away. 8 GB seems like a minimum to translate with Moses.