Robert, please elaborate why you say "To make best use of Cassandra, my minimum recommendation is usually RF=3, N=6."
I surmise that with any less than 6 nodes, you'd likely perform better with a sequential/single-node solution. You need at least six nodes to overcome the overheads from concurrency. But that's a vague explanation. Thanks, Don From: Robert Coli [mailto:rc...@eventbrite.com] Sent: Friday, March 07, 2014 11:36 AM To: user@cassandra.apache.org Subject: Re: replication_factor: ? On Fri, Mar 7, 2014 at 7:26 AM, Daniel Curry <daniel.cu...@arrayent.com<mailto:daniel.cu...@arrayent.com>> wrote: I would like to know on what is the rule of thumb for "replication_factor:" number? I think the answer is depends on how many nodes one has? IE: three nodes will be the number 3. What would happen it I put the number 2 for a three node cluster? To make best use of Cassandra, my minimum recommendation is usually RF=3, N=6. There are certainly valid use cases with lower RF or N but from what I can tell they are an order of magnitude less common. =Rob
