items does not write to disk

Install couchbase server 2.0.0dp4r-723 (with bucket deletion fix).
Use mcsoda load 2 million items with size 128, 256, 512, 1024, 50, 70 to cluster.
During the load running, create a design document with 2 views. Run map reduce to get total count result.
When the load was done, check disk write queue and see it up to 2 million items in queue. Drain rate is zero.
Waiting more than one hour without anyload, disk write queue does not go down.