Description
Old Document: http://www.mongodb.org/display/DOCS/Replica+Sets+-+Oplog
Potential New Document: http://docs.mongodb.org/manual/core/replication/#replica-set-oplog-sizing
Old Document: http://www.mongodb.org/display/DOCS/Replica+Sets+-+Oplog
Potential New Document: http://docs.mongodb.org/manual/core/replication/#replica-set-oplog-sizing