Last week’s SQL Server 2019 Cumulative Update 9 snuck in some undocumented things.
We got two new DMVs for Always On Availability Groups, sys.dm_hadr_cached_replica_states and sys.dm_hadr_cached_database_replica_states. They have a subset of data from other AG DMVs:
I sure wish I could point you to the documentation or KB article on those.
But we have no idea what changed in CU9 here, or why, or what to do about it.
I’m gonna be honest with you, dear reader: I’m starting to tell clients to choose SQL Server 2017 over SQL Server 2019. 2019 just doesn’t seem like it’s baked, and 2019’s Cumulative Updates have just become too large of a risk: the release notes aren’t honest about you’re deploying. That’s not fair to organizations that depend on SQL Server for mission critical deployments: they need to know what changed so they can be on the lookout for new unusual behaviors.
If your own developers were changing production without telling you how or why, you’d call them into the office, close the door, and have a conversation.
In lighter news, there are also a few new messages in sys.messages:
- 898: Buffer Pool scan took %I64d seconds: database ID %d, command ‘%ls’, operation ‘%ls’, scanned buffers %I64d, total iterated buffers %I64d, wait time %I64d ms. See ‘https://go.microsoft.com/fwlink/?linkid=2132602‘ for more information.
- 7877: Backup on secondary replica is not supported in the connection to contained availability group. Reconnect to SQL Instance and retry the operation.
- 8659: Cannot continue columnstore index build because it requires %I64d KB misc memory per thread, while the total memory grant for query is %I64d KB, total Columnstore bulk insert memory is limited to %I64d KB in query, and the maximum memory grant is limited to %I64d KB per query in workload group id=%ld and resource pool id=%ld. Retry after modifying columnstore index to contain fewer columns, or after increasing the maximum memory grant limit with Resource Governor.
- 35528: unable to read page due to invalid FCB
- 46933: PolyBase configuration is invalid or corrupt. Re-run PolyBase setup.