Prepared Statement Cache Size for Version 4 Style Data Sources in WebSphere Application Server V6.0 and V5.0 releases
 Technote (troubleshooting)
 
Problem(Abstract)
In IBM® WebSphere® Application Server V4.0, the prepared statement cache size setting is divided among connections. Version 4.0 style data sources used in WebSphere Application Server V5.0 releases behave differently.
 
Cause
For WebSphere Application Server V6.0 and V5.0 releases, whether using a version 4.0 or version 5.0 style data source, the statement cache size setting for a connection pool is the maximum number of prepared statements to cache for the data source per connection. This means that each connection can be allotted the number of prepared statements specified in the statement cache size.
 
Resolving the problem
Configure your version 4.0 style data source to have a statement cache size setting that is equal to the number of unique prepared statements the application will use. In WebSphere Application Server V4.0 releases, the statement cache size is a number shared among Connections.
For example, in V4.0 releases, if you had a statement cache size of 100 and 10 connections, each connection could have 10 prepared statements in the cache.

However, in V6.0 and V5.0 releases, if you had a statement cache size of 100 and 10 connections, each connection could have 100 prepared statements in the cache. Therefore, lowering the statement cache size to 10 would act like WebSphere Application Server V4.0 connection pool, where each connection would have 10 prepared statements available.

More detailed information on prepared statement cache size and memory usage can be found at:
Java_2_Connectivity__J2C_/swg21108496.html
 
 
Cross Reference information
Segment Product Component Platform Version Edition
Application Servers Runtimes for Java Technology Java SDK
 
 


Document Information


Product categories: Software > Application Servers > Distributed Application & Web Servers > WebSphere Application Server > DB Connections/Connection Pooling
Operating system(s): Windows
Software version: 6.0.2
Software edition:
Reference #: 1195924
IBM Group: Software Group
Modified date: Sep 2, 2007