You still have the same amount of RAM, so you cache the same amount of data. I don't think you gain much here. On the other side, maintenance procedures (compaction, repair) may hit your 2CPU box. I wouldn't do it.

Thank you,
  Andrey


On Wed, Aug 7, 2013 at 10:24 AM, Paul Ingalls <paulingalls@gmail.com> wrote:
Quick question about systems architecture.

Would it be better to run 5 nodes with 7GB RAM and 4CPU's or 10 nodes with 3.5GB RAM and 2CPUS?

I'm currently running the former, but am considering the latter.  My goal would be to improve overall performance by spreading the IO across more disks.  My currently cluster has low CPU utilization but does spend a good amount of time in iowait.  Would moving to more smaller nodes help with that?  Or would I run into trouble with the smaller ram and cpu?

Thanks!

Paul