PQ70308: PERFORMANCE ISSUES WHEN MANY ENTITY BEANS OF THE SAME TYPE ARE ACTIVATED. | |||||||||||||||||||||||||||||||||||||||||
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![]() APAR status Closed as program error. Error description Performance issues when many Entity beans of the same type are activated.Local fix Problem summary **************************************************************** * USERS AFFECTED: All users of WebSphere Application Server * * V4.0.1 for z/OS and OS/390 * **************************************************************** * PROBLEM DESCRIPTION: Customer reported peformance issues * * when accessing many instances of the * * the same bean type. * **************************************************************** * RECOMMENDATION: * **************************************************************** APAR PQ70308 addesses the following performance issues: 1) BeanIDs are inefficiently tested from start to end. When comparing different instances of the same beantype the unique information will be contained at the end of the bean id. 2) The Wrapper Cache makes a redundant lookup during insertion.Problem conclusion Support has been modified to address the performance issues documented in APAR PQ70308. APAR PQ70308 requires a change to documentation. This APAR requires changes to documentation. The following WebSphere Application Server V4.0.1 for z/OS and OS/390 publications will be changed: Operations and Administration (GA22-7835-06) Assembling J2EE Applications (SA22-7836-05) To access the latest online documentation, go to the product library page at: www.ibm.com/software/webservers/appserv/zos_os390/ WebSphere Application Server V4.0.1 for z/OS and OS/390 Operations and Administration (GA22-7835-06) will be changed as follows: Chapter 9. WebSphere for z/OS performance tuning guidelines Subtopic "Component management" Section "Java virtual machine properties file (jvm.properties):" Add the following bullet on page 114: o com.ibm.ejs.EJBCache.size -- provides the ability to tailor the EJB cache size. The impact on performance is workload dependent, and knowledge of entity bean usage is important in calculating the size of the EJB cache. - com.ibm.ejs.EJBCache.size=INT Note: The default value is 251. The value should be a prime number greater than 1. The EJB cache size should correspond to entity Bean usage. WebSphere Application Server V4.0.1 for z/OS and OS/390 Assembling J2EE Applications (SA22-7836-05) will be changed as follows: "Appendix A. Environment and JVM properties files" Topic "JVM properties and properties files" "Table 24. Where to use JVM properties" will be updated with the new entry for property "com.ibm.ejs.EJBCache.size=251" which is optional for only J2EE servers. "Appendix A. Environment and JVM properties files" Topic "Properties descriptions" on page 303 will be updated with the following new property description: com.ibm.ejs.EJBCache.size=number Sets the size of the Enterprise bean (EJB) cache. Recommendation: Calculate the cache size based on the workload of this J2EE server. The number that you specify for the size should correspond to the number of activated entity beans in the J2EE server. Default: 251 APAR PQ70308 is associated with SERVICE LEVEL W401501 of WebSphere Application Server V4.0.1 for z/OS and OS/390. **************************************************************** **************************************************************** **************************************************************** **************************************************************** ++HOLD for DOC APAR PQ70308 requires a change to documentation. This APAR requires changes to documentation. The following WebSphere Application Server V4.0.1 for z/OS and OS/390 publications will be changed: Operations and Administration (GA22-7835-06) Assembling J2EE Applications (SA22-7836-05) To access the latest online documentation, go to the product library page at: www.ibm.com/software/webservers/appserv/zos_os390/ WebSphere Application Server V4.0.1 for z/OS and OS/390 Operations and Administration (GA22-7835-06) will be changed as follows: Chapter 9. WebSphere for z/OS performance tuning guidelines Subtopic "Component management" Section "Java virtual machine properties file (jvm.properties):" Add the following bullet on page 114: o com.ibm.ejs.EJBCache.size -- provides the ability to tailor the EJB cache size. The impact on performance is workload dependent, and knowledge of entity bean usage is important in calculating the size of the EJB cache. - com.ibm.ejs.EJBCache.size=INT Note: The default value is 251. The value should be a prime number greater than 1. The EJB cache size should correspond to entity Bean usage. WebSphere Application Server V4.0.1 for z/OS and OS/390 Assembling J2EE Applications (SA22-7836-05) will be changed as follows: "Appendix A. Environment and JVM properties files" Topic "JVM properties and properties files" "Table 24. Where to use JVM properties" will be updated with the new entry for property "com.ibm.ejs.EJBCache.size=251" which is optional for only J2EE servers. "Appendix A. Environment and JVM properties files" Topic "Properties descriptions" on page 303 will be updated with the following new property description: com.ibm.ejs.EJBCache.size=number Sets the size of the Enterprise bean (EJB) cache. Recommendation: Calculate the cache size based on the workload of this J2EE server. The number that you specify for the size should correspond to the number of activated entity beans in the J2EE server. Default: 251Temporary fix Comments
APAR is sysrouted FROM one or more of the following: APAR is sysrouted TO one or more of the following: Modules/Macros
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Document Information |
Product categories: Software > Application Servers >
Distributed Application & Web Servers > WebSphere Application
Server for z/OS
Operating system(s):
Software version: 401
Software edition:
Reference #: PQ70308
IBM Group: Software Group
Modified date: Apr 3, 2003
(C) Copyright IBM Corporation 2000, 2006. All Rights Reserved.