Database Tuning Question

I've been noticing a large number of CI's in the "Total Discovered CI's in Sending Queue" for several of my probes.  Since I recently migrated the database from our test environment to our production environment I suspect the issue may be the database.  While trying to track down the issue I found the following statement multiple times in the cmdb.dal log; Failed optimized joinf Query, falling back to standard joinf query.  Any ideas what this is and whether I should be concerned.