When you use Always On Availability Groups in Microsoft SQL Server 2016 or 2017, the parallel recovery of the readable secondary replica is suspended if there are concurrent read-only queries on the same replica, and you receive the following error message:

Date\Time SPID A time-out occurred while waiting for buffer latch -- type 4, bp 000000E66DA93540, page PageID, stat 0xb, database id: DatabaseID, allocation unit Id: UnitID, task TaskID, waittime 300 seconds, flags 0x1018, owning task TaskID. Not continuing to wait.


This issue is fixed in the following cumulative updates for SQL Server:

       Cumulative Update 6 for SQL Server 2017 

       Cumulative update 8 for SQL Server 2016 SP1

Each new cumulative update for SQL Server contains all the hotfixes and all the security fixes that were included with the previous cumulative update. Check out the latest cumulative updates for SQL Server:

Latest cumulative update for SQL Server 2017

Latest cumulative update for SQL Server 2016


To work around this issue, use one of the following methods:

  • Avoid the primary replica and secondary replica working on the same table at the same time.

  • Set a query time-out to exit the query when it has been executed for 1 or 2 minutes.

  • Reduce the MAXDOP.


Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.


Learn about the terminologythat Microsoft uses to describe software updates.

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