http://www.mail-archive.com/user@cassandra.apache.org/msg26528.html
From: Alain RODRIGUEZ <arodr...@gmail.com<mailto:arodr...@gmail.com>> Reply-To: "user@cassandra.apache.org<mailto:user@cassandra.apache.org>" <user@cassandra.apache.org<mailto:user@cassandra.apache.org>> Date: Friday, January 4, 2013 6:00 AM To: "user@cassandra.apache.org<mailto:user@cassandra.apache.org>" <user@cassandra.apache.org<mailto:user@cassandra.apache.org>> Subject: num_tokens - virtual nodes Hi, I just discover the vnodes new feature described here: http://www.datastax.com/dev/blog/virtual-nodes-in-cassandra-1-2 In the post above, Brandon says "If you’d like to upgrade an installation to virtual nodes, that’s possible too, but I’ll save that for a later post". Does this post now exist somewhere ? From the cassandra.yaml: # If you already have a cluster with 1 token per node, and wish to migrate to # multiple tokens per node, see http://wiki.apache.org/cassandra/Operations # num_tokens: 256 I see no reference to vnodes or num_tokens on this wiki. So, how to switch from "physical" nodes to vnodes ? This is useful only if your number of nodes is greater than the RF, right ? Why 256 token by default ? Where this value come from ? Is there more advantage / disadvantage of using vnodes that improving the internodes data streaming by increasing the number of data sources ? Alain Southfield Public School students safely access the tech tools they need on and off campus with the Barracuda Web Filter. Quick installation and easy to use- try the Barracuda Web Filter free for 30 days: http://on.fb.me/Vj6JBd
