Microsoft KB Archive/818767

= FIX: Improved CPU Usage for Database Logging When Transaction Log Stalls Occur =

Article ID: 818767

Article Last Modified on 10/25/2005

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APPLIES TO


 * Microsoft SQL Server 2000 Service Pack 3
 * Microsoft Windows 2000 Standard Edition

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BUG #: 469415 (SQL Server 8.0)



SYMPTOMS
If transaction log stalls occur, a computer running SQL Server may experience CPU usage that was not expected. This usage occurs because of poor log file performance or because database backups are in progress.



Service pack information
To resolve this problem, obtain the latest service pack for Microsoft SQL Server 2000. For additional information, click the following article number to view the article in the Microsoft Knowledge Base:

290211 How to obtain the latest SQL Server 2000 service pack

Hotfix information
The English version of this fix has the file attributes (or later) that are listed in the following table. The dates and times for these files are listed in coordinated universal time (UTC). When you view the file information, it is converted to local time. To find the difference between UTC and local time, use the Time Zone tab in the Date and Time tool in Control Panel.   Date         Time   Version            Size    File name --  26-Feb-2003  03:41  2000.80.777.0      29,244  Dbmslpcn.dll 25-Apr-2003 02:12                    786,432  Distmdl.ldf 25-Apr-2003 02:12                  2,359,296  Distmdl.mdf 30-Jan-2003 01:55                        180  Drop_repl_hotfix.sql 07-Apr-2003 19:15  2000.80.801.0   1,557,052  Dtsui.dll 24-Apr-2003 02:51                    747,927  Instdist.sql 30-Jan-2003 01:55                      1,402  Inst_repl_hotfix.sql 08-Feb-2003 06:40  2000.80.765.0      90,692  Msgprox.dll 01-Apr-2003 02:07                      1,873  Odsole.sql 05-Apr-2003 01:46  2000.80.800.0      62,024  Odsole70.dll 02-Apr-2003 21:48  2000.80.796.0      57,904  Osql.exe 02-Apr-2003 23:15  2000.80.797.0     279,104  Pfutil80.dll 04-Apr-2003 21:27                  1,083,467  Replmerg.sql 04-Apr-2003 21:53  2000.80.798.0     221,768  Replprov.dll 08-Feb-2003 06:40  2000.80.765.0     307,784  Replrec.dll 01-Apr-2003 02:23                  1,084,828  Replsys.sql 16-Apr-2003 22:39                    115,892  Sp3_serv_uni.sql 07-Apr-2003 17:44                     25,172  Sqldumper.exe 19-Mar-2003 18:20  2000.80.789.0      28,672  Sqlevn70.rll 24-Apr-2003 05:39  2000.80.811.0     176,696  Sqlmap70.dll 08-Feb-2003 06:40  2000.80.765.0      57,920  Sqlrepss.dll 30-Apr-2003 23:52  2000.80.816.0   7,540,817  Sqlservr.exe 08-Feb-2003 06:40  2000.80.765.0      45,644  Sqlvdi.dll 26-Feb-2003 03:41  2000.80.777.0      29,244  Ssmslpcn.dll 26-Feb-2003 03:41  2000.80.777.0      82,492  Ssnetlib.dll 30-Apr-2003 23:52  2000.80.816.0      45,132  Ums.dll 28-Feb-2003 01:34  2000.80.778.0      98,872  Xpweb70.dll Note Because of file dependencies, the most recent hotfix or feature that contains these files may also contain additional files.



STATUS
Microsoft has confirmed that this is a problem in the Microsoft products that are listed at the beginning of this article. This problem was first corrected in Microsoft SQL Server 2000 Service Pack 4.



MORE INFORMATION
The problem can be triggered by snapshot backups because the snapshot backup process involves the freeze and thaw of I/O operations. The freeze activity holds up all physical I/O activity until the thaw is issued at the end of the snapshot backup operation. In doing so, a code change that was made in SQL Server 2000 Service Pack 2 (SP2) results in heavier CPU usage than in earlier versions of SQL Server. The scalability change in SQL Server 2000 SP2 makes the log code scale better on multiprocessor computers. This change can, however, result in heavier CPU usage under rare conditions.

Keywords: kbhotfixserver kbqfe kbqfe kbsqlserv2000presp4fix kbfix kbbug KB818767

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