On Wed, 20 Jan 2010 21:14:27 -0600 Jonathan Ellis <jbel...@gmail.com> wrote:
JE> On Wed, Jan 20, 2010 at 9:10 PM, Phillip Michalak JE> <phil.micha...@digitalreasoning.com> wrote: >> Does anyone have a recommendation for configuring cassandra on a cluster >> with 'large' nodes? >> i.e. multiple nodes, each >64G RAM, 8 cores, >4 disks >> >> Would it be better to run multiple cassandra processes per node (configured >> on separate IP addresses, separate data directories, etc) or just a single >> mammoth cassandra process on each node? Is there an upper bound on what >> you'd want to allocate to a cassandra process? JE> assuming that you're planning to use most of the ram for read caching JE> and not for the JVM process, I don't see any advantage to justify the JE> extra complexity of running multiple processes per machine. JE> (I only mention that caveat because I don't know how well the JVM JE> scales to heaps that large.) Sun mentions garbage collection issues in the HotSpot FAQ: http://java.sun.com/docs/hotspot/HotSpotFAQ.html#64bit_description Based on that, it seems like a good idea to enable the parallel or concurrent garbage collectors with large heaps. We're looking at this at our site as well so I'm curious about people's experiences. Ted
