We used Hbase Performance evaluation test class.
Test cluster had 10 nodes, each node had 4G of RAM and 2x dual-core 2Ghz Opterons.
Hadoop DataNode, TaskTracker, Neptune TabletServer, ChangelogServer ran on each node.
One node was master node which ran the NameNode, the NeptuneMaster and the Zookeeper Server.
Test program ran on that master node.
Test program write 1,048,576 rows(1GB): each row has a single column whose value is 1,000 randomly-generated bytes.

Experiment	Neptune(2009.05.18)
Random read	495
Random write	1,223
Sequential read	498
Sequential write	1,327
Scan	40,329