PQ63551: SESSION MANAGER DOES NOT USE PREPAREDSTATEMENT OBJECTS FOR THE SELECT STATEMENTS IN THE INVALIDATION THREAD | |||||||||||||||||||||||||||||||||||||
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APAR status Closed as program error. Error description The Invalidation Thread of the Session Manager does not use the PreparedStatement object for the SELECT statements (the SELECT statements use the normal Statement objects): select id , lastaccess from sessions where ( listenercnt = 0 and maxinactivetime >= 0 and ( 1017099692809 - (maxinactivetime * 1000)) > lastaccess) . select id, lastaccess from sessions where ( appname = 'SDCSWebApp' and listenercnt > 0 and maxinactivetime >= 0 and ( 1017099692793 - (maxinactivetime * 1000)) > lastaccess) . When using the Statement objects repeatly (every 2-3 minutes), this causes the Oracle memory to be fragmented (the memory is free not unallocated)Local fix Problem summary **************************************************************** * USERS AFFECTED: WebSphere Application Server - Session * * Manager Users * **************************************************************** * PROBLEM DESCRIPTION: Ordinary JDBC select statements being * * executed in the invalidation path * * were causing the Oracle database * * memory to be fragmented. * **************************************************************** * RECOMMENDATION: * **************************************************************** The invalidation thread in the session manager runs normally every 3-4 minutes by default. As part of the invalidation process, select statements are executed to obtain the eligible session candidate list for invalidation. We were using simple jdbc statements to execute the select statement which was reported to have caused memory fragmentation in Oracle.Problem conclusion In this fix the simple statements were changed to prepared statements which will get reused for the execution of these select statements which should help in reducing Oracle memory fragmentation.Temporary fix PQ59674.jarComments
APAR is sysrouted FROM one or more of the following: PQ59674 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 > General
Operating system(s):
Software version: 400
Software edition:
Reference #: PQ63551
IBM Group: Software Group
Modified date: Jul 25, 2002
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