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jdrowell # do I need lots of RAM to be performant? the innodb tuning wiki mentions gigs of RAM. I planned to deploy riak on small slices (like 512MB RAM)

bingeldac # that would depend on the amount of keys more than anything
512 is a little small, but if you don't have a ton of data it should perform ok
though VMs have slow I/O

bingeldac # and that will slow you down regardless of the amount of data you have

jdrowell # k. I have lots of keys. does riak keep them in RAM (like redis does)?

bingeldac # no, it is on disk

jdrowell # y agreed VM I/O is slow

bingeldac # but you will have a smaller inno buffer bache cache
jdrowell # got it

jdrowell # what about the number of nodes, can I start with 2 or should I have more for the R and W parameters to really work?

bingeldac # no but one node will have 2 vnodes so R, N, W don't correspond to the number of machines

jdrowell # k. that's internal to riak, right? I don't have to run 2 instances of it?

bingeldac # they correspond to the number of vnodes and vnodes move around from node to node as needed to things like handoff. So with a default N of 3 you will have one host with 2 vnodes and one with 1

jdrowell # cool

bingeldac # so, if you have an r and w of 3 and one machines dies you could be in a spot where you couldn't read

jdrowell # I see. unless I use R=2

bingeldac # I would recommend using a lower r perhaps to insulate yourself a little well even then one machine has 2 vnodes if it dies

jdrowell # y if the machine with 2 vnodes goes down...

bingeldac # you could have paitions of data in each vnode yeah
i gotta run to soccer games for my kiddos. I will be around later tonight if you have more questions or as always riak-users list, many users respond faster than us it seems :)

bingeldac # thank god for community

jdrowell # tks for your help :