RackUnaware, currently On Tue, Jun 22, 2010 at 1:26 PM, Robert Coli <rc...@digg.com> wrote:
> On 6/22/10 10:07 AM, James Golick wrote: > >> This node's load is now growing at a ridiculous rate. It is at 105GB, with >> the next most loaded node at 70.63GB. >> >> Given that RF=3, I would assume that the replicas' nodes would grow >> relatively quickly too? >> > What Replica Placement Strategy are you using (Rackunaware, Rackaware, > etc?)? The current implementation of Rackaware is pretty simple and relies > on careful placement of nodes in multiple DCs along the ring to avoid > hotspots. > > http://wiki.apache.org/cassandra/Operations#Replication > " > RackAwareStrategy: replica 2 is placed in the first node along the ring the > belongs in another data center than the first; the remaining N-2 replicas, > if any, are placed on the first nodes along the ring in the same rack as the > first > > Note that with RackAwareStrategy, succeeding nodes along the ring should > alternate data centers to avoid hot spots. For instance, if you have nodes > A, B, C, and D in increasing Token order, and instead of alternating you > place A and B in DC1, and C and D in DC2, then nodes C and A will have > disproportionately more data on them because they will be the replica > destination for every Token range in the other data center. > " > > https://issues.apache.org/jira/browse/CASSANDRA-785 > > Is also related, and marked Fix Version 0.8. > > =Rob > >
