FIX: DBCC TEXTALLOC May Cause SQL Server to Stop Responding

Under memory constrained conditions, running DBCC TEXTALLOC against a table containing large text values may cause SQL Server to stop processing queries and logon requests. SQL Server may also write indefinite bufwait messages or write an access violation stack dump to the errorlog in some cases. SQL Server may not seem to be responding and will not allow processing until the service is stopped and restarted.

Read-ahead was being used for the text and not the base table.

Microsoft has confirmed this to be a problem in SQL Server version 6.5. This problem has been corrected in the Post Service Pack 5a Update for Microsoft SQL Server version 6.5. To install the Post Service Pack 5a Update, you must have either SQL Server 6.5 SP5 or SP5a installed.

For information about how to download and install the SQL Server 6.5 Service Pack 5a, refer to the following article in the Microsoft Knowledge Base: If you already have SQL Server 6.5 SP5 or SP5a installed, you can download the Post SP5a Update from the following article in the Microsoft Knowledge Base: For more information, contact your primary support provider.

The following error may be written to the errorlog, which may cause a concern for reconfiguring sp_configure settings: Increasing the read ahead settings may provide some immediate relief, but the likelihood of reoccurrence is increased as more text is added to the table.