There are some good recommendations in this blog post:
It's a little dated, but the reasoning and basics are sound.
On Thu, Jun 9, 2011 at 10:59 AM, Mark <[EMAIL PROTECTED]> wrote:
> Can someone give some brief guidance on some (ballpark) specs for a hadoop
> - What are the typical size and memory requirements are there for a
> dedicated namenode?
> - What are the typical size and memory requirements are there for individual
> - Should there be more, less or even amounts of ram on each datanode?
> - Should the namenode have more, less or an even amount of ram as compared
> to the datanode?