INF: SQL70IOStress Utility to Stress Disk Subsystem

ID: Q231619

The information in this article applies to:

SUMMARY

You can use the SQL70IOStress utility to perform stress tests on a disk subsystem to simulate SQL Server 7.0 read and write activity. This utility is located at:

http://support.microsoft.com/support/downloads/LNP220.asp


MORE INFORMATION

The utility is specifically designed to simulate the read and write patterns of a heavily loaded SQL Server. Testing shows that if the utility approaches 70 writes/sec you should highly consider it to be a write cache enabled drive.

The section below is an excerpt from the SQL70IOStress during a power outage test with a caching IDE drive under Windows NT 4.0 Service Pack 4. Notice that the torn write shows the older LSN for the last three sectors of the 8 KB page.

NOTE: The actual sector data is removed for clarity; the utility will actually dump the sector data as well.) 


04/20/99 16:28:26 00000154	ERROR: LSN for page 3292 is out of sequence.  Expected: 16447 and found 10049 in sector 15.  Probably a torn page.
04/20/99 16:28:26 00000154	
04/20/99 16:28:26 00000154	---------------------------------------------------------------
04/20/99 16:28:26 00000154	ERROR: Did not find expected pattern in file for page 3292.
04/20/99 16:28:26 00000154	Bytes read = 8192
04/20/99 16:28:26 00000154	Potential torn write
04/20/99 16:28:26 00000154	---------------------------------------------------------------
04/20/99 16:28:26 00000154	Sector: 0      LSN: 16447
04/20/99 16:28:26 00000154	---------------------------------------------------------------------------
04/20/99 16:28:26 00000154	Sector: 1      LSN: 16447
04/20/99 16:28:26 00000154	---------------------------------------------------------------------------
04/20/99 16:28:26 00000154	Sector: 2      LSN: 16447
04/20/99 16:28:26 00000154	---------------------------------------------------------------------------
04/20/99 16:28:26 00000154	Sector: 3      LSN: 16447
04/20/99 16:28:26 00000154	---------------------------------------------------------------------------
04/20/99 16:28:26 00000154	Sector: 4      LSN: 16447
04/20/99 16:28:26 00000154	---------------------------------------------------------------------------
04/20/99 16:28:26 00000154	Sector: 5      LSN: 16447
04/20/99 16:28:26 00000154	---------------------------------------------------------------------------
04/20/99 16:28:26 00000154	Sector: 6      LSN: 16447
04/20/99 16:28:26 00000154	---------------------------------------------------------------------------
04/20/99 16:28:26 00000154	Sector: 7      LSN: 16447
04/20/99 16:28:26 00000154	---------------------------------------------------------------------------
04/20/99 16:28:26 00000154	Sector: 8      LSN: 16447
04/20/99 16:28:26 00000154	---------------------------------------------------------------------------
04/20/99 16:28:26 00000154	Sector: 9      LSN: 16447
04/20/99 16:28:26 00000154	---------------------------------------------------------------------------
04/20/99 16:28:26 00000154	Sector: 10      LSN: 16447
04/20/99 16:28:26 00000154	---------------------------------------------------------------------------
04/20/99 16:28:26 00000154	Sector: 11      LSN: 16447
04/20/99 16:28:26 00000154	---------------------------------------------------------------------------
04/20/99 16:28:26 00000154	Sector: 12      LSN: 16447
04/20/99 16:28:26 00000154	---------------------------------------------------------------------------
04/20/99 16:28:26 00000154	Sector: 13      LSN: 10049
04/20/99 16:28:26 00000154	---------------------------------------------------------------------------
04/20/99 16:28:26 00000154	Sector: 14      LSN: 10049
04/20/99 16:28:26 00000154	---------------------------------------------------------------------------
04/20/99 16:28:26 00000154	Sector: 15      LSN: 10049
04/20/99 16:28:26 00000154	---------------------------------------------------------------------------
04/20/99 16:28:26 00000154	
04/20/99 16:28:26 00000154	ERROR: Appears to be a premature truncation of file.  Pages expected: 6400, Pages Read: 3292, Last Error: 0
04/20/99 16:28:26 00000154	Current LSN is 16447
If you have any concerns about the stability of your data due to caching mechanisms of the drive or controller, enable the Torn Page Detection database option and contact the appropriate manufacturer(s) for the utilities needed to disable write caching.

For additional information, please see the following article in the Microsoft Knowledge Base:
Q230785 INF: SQL Server 7.0 Logging and Data Storage Algorithms Extend Data Reliability
For complete parameter and usage details, run the SQL70IOStress utility with the ? parameter to get complete help.

Additional query words: SQL70IOStress.exe 


Keywords          : 
Version           : winnt:7.0
Platform          : winnt 
Issue type        : kbinfo

Last Reviewed: July 7, 1999