Author: jbellis
Date: Mon Jan 3 14:27:38 2011
New Revision: 1054630
URL: http://svn.apache.org/viewvc?rev=1054630&view=rev
Log:
update Partitioner explanation
Modified:
cassandra/branches/cassandra-0.7.0/conf/cassandra.yaml
Modified: cassandra/branches/cassandra-0.7.0/conf/cassandra.yaml
URL:
http://svn.apache.org/viewvc/cassandra/branches/cassandra-0.7.0/conf/cassandra.yaml?rev=1054630&r1=1054629&r2=1054630&view=diff
==============================================================================
--- cassandra/branches/cassandra-0.7.0/conf/cassandra.yaml (original)
+++ cassandra/branches/cassandra-0.7.0/conf/cassandra.yaml Mon Jan 3 14:27:38
2011
@@ -38,14 +38,28 @@ authenticator: org.apache.cassandra.auth
# authorization backend, implementing IAuthority; used to limit access/provide
permissions
authority: org.apache.cassandra.auth.AllowAllAuthority
-# any IPartitioner may be used, including your own as long as it is on
-# the classpath. Out of the box, Cassandra provides
-# org.apache.cassandra.dht.RandomPartitioner
+# The partitioner is responsible for distributing rows (by key) across
+# nodes in the cluster. Any IPartitioner may be used, including your
+# own as long as it is on the classpath. Out of the box, Cassandra
+# provides org.apache.cassandra.dht.RandomPartitioner
# org.apache.cassandra.dht.ByteOrderedPartitioner,
-# org.apache.cassandra.dht.OrderPreservingPartitioner, and
-# org.apache.cassandra.dht.CollatingOrderPreservingPartitioner.
-# (CollatingOPP colates according to EN,US rules, not naive byte
-# ordering. Use this as an example if you need locale-aware collation.)
+# org.apache.cassandra.dht.OrderPreservingPartitioner (deprecated),
+# and org.apache.cassandra.dht.CollatingOrderPreservingPartitioner
+# (deprecated).
+#
+# - RandomPartitioner distributes rows across the cluster evenly by md5.
+# When in doubt, this is the best option.
+# - ByteOrderedPartitioner orders rows lexically by key bytes. BOP allows
+# scanning rows in key order, but the ordering can generate hot spots
+# for sequential insertion workloads.
+# - OrderPreservingPartitioner is an obsolete form of BOP, that stores
+# - keys in a less-efficient format and only works with keys that are
+# UTF8-encoded Strings.
+# - CollatingOPP colates according to EN,US rules rather than lexical byte
+# ordering. Use this as an example if you need custom collation.
+#
+# See http://wiki.apache.org/cassandra/Operations for more on
+# partitioners and token selection.
partitioner: org.apache.cassandra.dht.RandomPartitioner
# directories where Cassandra should store data on disk.
