Hi Cihan,
This doc specifies:
The following hardware requirements are recommended for installation: ... 16GB RAM (physical) ... A minimum specification machine should have the following characteristics: 4GB RAM (physical)
The 2GB for XDCR comment came from this blog post:
I’ll take separate looks at the “source” and “destination” cluster requirements for XDCR ... It will vary a bit based on how many buckets (and replication streams) but a good estimate is to leave about 2GB of RAM free per node above and beyond what is needed to hold the data.
If I could reliably run a production cluster with a half gig to a gig of data on 2GB boxes (or 4GB boxes) I’d be pretty happy. 16GB seems crazy over the top for that amount of data.