FIX: Performance enhancements to the Host Integration Server 2004 DB2 Providers (888425)


The information in this article applies to:

  • Microsoft Host Integration Server 2004

SUMMARY

Based on customer feedback, the Microsoft Host Integration Server 2004 DB2 network client and data providers have been improved to enhance performance in complex customer scenarios. For example, these scenarios could include the following:
  • Microsoft SQL Server replication and distributed queries
  • Most cases of Client Cursor Engines (CCEs). With CCEs, applications that use data use prepared SQL statements and manual remote unit of work (RUW) commits.

RESOLUTION

A supported feature that modifies the product's default behavior is now available from Microsoft, but it is only intended to modify the behavior that this article describes. Apply it only to systems that specifically require it. This feature may receive additional testing. Therefore, if the system is not severely affected by the lack of this feature, we recommend that you wait for the next Host Integration Server 2004 service pack that contains this feature.

To obtain this feature immediately, contact Microsoft Product Support Services. For a complete list of Microsoft Product Support Services telephone numbers and information about support costs, visit the following Microsoft Web site:

http://support.microsoft.com/contactus/?ws=support

The English version of this hotfix has the file attributes (or later file attributes) 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
   ------------------------------------------------------------------------------------------
   09-Dec-2004  00:41  6.0.1918.0    486,912  Db2oledb.dll     
   09-Dec-2004  00:46                 24,516  Db2oledb.h
   09-Dec-2004  18:10  6.0.1918.0     86,016  Microsoft.hostintegration.dataaccesslibrary.dll  
   09-Dec-2004  18:10  6.0.1918.0  2,703,360  Microsoft.hostintegration.dataaccesstool.exe  
   09-Dec-2004  18:10  6.0.1918.0    114,688  Microsoft.hostintegration.msdb2client.dll  
   09-Dec-2004  00:41  6.0.1918.0     71,680  Mseidb2c.dll     
   09-Dec-2004  00:41  6.0.1918.0    435,200  Mseidb2d.dll     
   09-Dec-2004  00:41  6.0.1918.0    684,032  Mseidrda.dll

Note Because of file dependencies, the most recent fix that contains these files may also contain additional files.

MORE INFORMATION

When this hotfix runs against DB2 for z/OS and DB2 UDB platforms, this hotfix combines the PREPARE, EXECUTE, and COMMIT wire level distributed relational database architecture (DRDA) flows into one flow for each parameterized INSERT, UPDATE, or DELETE statement that is issued by the application that is using the data. When this hotfix runs against all DB2 platforms, the hotfix combines the PREPARE and EXECUTE wire level DRDA flows into one flow for each parameterized SELECT statement. This change can reduce overall execution time when you are running many prepared SQL commands.

To use this fix, you must set an optional "connection parameter." This parameter could be a property, an attribute, or an option in the user interface. For more information, see the section for each data access architecture.

Microsoft OLE DB Provider for DB2

Property group: Initialization
Property set: DBPROPSET_DBINIT
Property ID: DBPROP_DB2OLEDB_DEFPREP
Property description: Defer Prepare
Default value: FALSE
Type: VT_BOOL
R/W: R/W
Default: FALSE
Required: No
Data Links dialog: All
Data Links control type: Drop-down list
Data Links control label: Defer Prepare
Explanation: Instructs the provider to optimize the processing of parameterized INSERT, UPDATE, DELETE, and SELECT commands. For the INSERT, UPDATE, and DELETE commands, the provider will combine the prepare, execute, and commit commands together into one network flow to the remote database. For the SELECT command, the provider will combine the prepare and execute commands into one network flow. This optimization will minimize network traffic and frequently improve overall performance.

Microsoft ODBC Driver for DB2

Connection attribute keyword: DFP
Registry DSN keyword: Defer Prepare
Type: Boolean
R/W: R/W
Default: FALSE
Supported values: TRUE, FALSE
Required: No
Driver Manager dialog: Target Database
Driver Manager control type: Check box
Driver Manager control label: Defer Prepare
Explanation: Instructs the provider to optimize the processing of parameterized INSERT, UPDATE, DELETE, and SELECT commands. For the INSERT, UPDATE, and DELETE commands, the provider will combine the prepare, execute, and commit commands together into one network flow to the remote database. For the SELECT command, the provider will combine the prepare and execute commands into one network flow. This optimization will minimize network traffic and frequently improve overall performance.

Managed Provider for DB2

Class: MsDb2Connection
Property: DeferPrepare
Type: Boolean
Default: FALSE
Explanation: Instructs the provider to optimize the processing of parameterized INSERT, UPDATE, DELETE, and SELECT commands. For the INSERT, UPDATE, and DELETE commands, the provider will combine the prepare, execute, and commit commands together into one network flow to the remote database. For the SELECT command, the provider will combine the prepare and execute commands into one network flow. This optimization will minimize network traffic and frequently improve overall performance.

Data Source Wizard

Dialog: Advanced Options
Control type: Check box
Control label: Defer Prepare
Default: FALSE
Supported Values: TRUE, FALSE
Required: No
Help text: Defer prepare reduces the number of network packets by delaying when prepare commands are sent to the database.

Data Access Library

Class: IConnectionString
Property: DeferPrepare
Type: Boolean
Default: FALSE
Explanation: Instructs the provider to optimize the processing of parameterized INSERT, UPDATE, DELETE, and SELECT commands. For the INSERT, UPDATE, and DELETE commands, the provider will combine the prepare, execute, and commit commands together into one network flow to the remote database. For the SELECT command, the provider will combine the prepare and execute commands into one network flow. This optimization will minimize network traffic and frequently improve overall performance.

Background Information

This change does not affect calling stored procedures where the DB2 network client (DRDA AR) does not prepare the CALL statement.
Modification Type:MinorLast Reviewed:6/5/2006
Keywords:kbHotfixServer kbQFE kbfix kbBug kbinfo KB888425 kbAudDeveloper kbAudITPRO
©2004 Microsoft Corporation. All rights reserved.