FIX: Unhandled AV During Concurrent DUMP DATABASE Commands

• Microsoft SQL Server version 6.5

SYMPTOMS

An unhandled access violation (AV) with the stack trace shown below may occur very infrequently while two or more concurrent DUMP DATABASE commands are running. Due to the unhandled nature of the AV, the stack trace will only be visible if the Windows NT Server symbols are installed and either of the following conditions are true:

• You are running the server under a debugger.
  
  -or-



• A just-in-time debugger attaches to the SQL process upon the AV.

   ntdll!RtlUnwind+0xd2
   MSVCRT40!global_unwind2+0x18
   MSVCRT40!longjmpex+0x18 

WORKAROUND

Current evidence indicates the problem may occur when an attention event, such as dbcancel(), is received when two or more database dumps are running. Try running the dumps in series instead of in parallel. If this is not sufficient, try to avoid query cancellation during database dump. If this is not possible, put the server in single-user mode before doing a database dump.

STATUS

Microsoft has confirmed this to be a problem in SQL Server version 6.5. This problem was corrected in the latest Microsoft SQL Server 6.5 U.S. Service Pack. For information on obtaining the service pack, query on the following word in the Microsoft Knowledge Base (without the spaces):

S E R V P A C K

Keywords : kbenv kbusage SSrvGen SSrvGPF kbbug6.50 kbfix6.50.sp4
Version : 6.5
Platform : WINDOWS
Issue type : kbbug