MB-100: unbounded read ops analysis

Change-Id: I90146b7c24fbc5fa32c30a6d9f50caa62b9a53d1
Reviewed-on: http://review.couchbase.org/28311
Reviewed-by: Ronnie Sun <ronnie@couchbase.com>
Tested-by: Ronnie Sun <ronnie@couchbase.com>