AlwaysOn Availability Groups log_send_rate On all our AlwaysOn setups, running Windows 2012 and SQL Server 2012 in virtual machines and on bare-metal, I find that the log_send_rate in
sys.dm_hadr_database_replica_states is consistently returning incorrect values.

For example (for synchronous mode)

sys.dm_hadr_database_replica_states.log_send_rate (ave = 36,571 (kb/s listed in bol))

Perfmon - SQLServer:Availability Replica - Bytes Sent to Replica/sec (max = 486,000.000, avg = 259,000.000)

Perfmon - SQLServer:Databases - Log Bytes Flushed/sec  (max = 653,044.000, avg = 341,000.000)

I've not seen any posts about this but it doesn't appear to be working correctly. A correct log_send_rate value is useful for monitoring AlwaysOn.

Has anyone else experienced this?
Yes, this was fixed recently in Service Pack 2, Cumulative Update 3. Here's the KB article: http://support.microsoft.com/kb/3012182

"FIX: Log_Send_Rate column in sys.dm_hadr_database_replica_states cannot reflect the rate accurately in SQL Server 2012"