When I was trying to running the server on my VM (2G memory), it shows 

```

…

java.lang.OutOfMemoryError

Java HotSpot(TM) 64-Bit Server VM warning: INFO: os::commit_memory(0x00007f4d913cc000, 12288, 0) failed; error='Cannot allocate memory' (errno=12)

```

Wondering how much memory & CPU is sufficient for it?

Thanks!