Fixes are available
19.0.0.1: WebSphere Application Server Liberty 19.0.0.1
19.0.0.2: WebSphere Application Server Liberty 19.0.0.2
19.0.0.3: WebSphere Application Server Liberty 19.0.0.3
19.0.0.4: WebSphere Application Server Liberty 19.0.0.4
19.0.0.5: WebSphere Application Server Liberty 19.0.0.5
19.0.0.6: WebSphere Application Server Liberty 19.0.0.6
19.0.0.7: WebSphere Application Server Liberty 19.0.0.7
19.0.0.8: WebSphere Application Server Liberty 19.0.0.8
19.0.0.9: WebSphere Application Server Liberty 19.0.0.9
19.0.0.10: WebSphere Application Server Liberty 19.0.0.10
19.0.0.11: WebSphere Application Server Liberty 19.0.0.11
19.0.0.12: WebSphere Application Server Liberty 19.0.0.12
20.0.0.1: WebSphere Application Server Liberty 20.0.0.1
20.0.0.2: WebSphere Application Server Liberty 20.0.0.2
20.0.0.3: WebSphere Application Server Liberty 20.0.0.3
20.0.0.4: WebSphere Application Server Liberty 20.0.0.4
20.0.0.5: WebSphere Application Server Liberty 20.0.0.5
APAR status
Closed as program error.
Error description
ConcurrentModificationException happens when a web application receives a large number of requests immediately after it starts. Caused by: java.util.ConcurrentModificationException at java.util.ArrayList$Itr.checkForComodification(ArrayList.jav a:91 2) at java.util.ArrayList$Itr.next(ArrayList.java:862) at com.ibm.ws.webcontainer.util.MetaInfResourcesFileUtils.<init >(Me taInfResourcesFileUtils.java:81) at com.ibm.ws.webcontainer.util.DocumentRootUtils.getMetaInfRes (Doc umentRootUtils.java:492) at com.ibm.ws.webcontainer.util.DocumentRootUtils.handleDocumen tRoo ts(DocumentRootUtils.java:204) at com.ibm.ws.webcontainer.util.DocumentRootUtils.handleDocumen tRoo ts(DocumentRootUtils.java:171) at com.ibm.ws.webcontainer.osgi.webapp.WebApp.getResourceAsStre am(W ebApp.java:544) at com.ibm.wsspi.webcontainer.facade.ServletContextFacade.getRe sour ceAsStream(ServletContextFacade.java:158) ... 105 more Problem first reported on Liberty 17.0.0.3 and also recreated on 18.0.0.3
Local fix
Problem summary
**************************************************************** * USERS AFFECTED: All users of IBM WebSphere Application * * Server Liberty * **************************************************************** * PROBLEM DESCRIPTION: ConcurrentModificationException might * * occur with a large number of requests * * immediately after application is * * started. * **************************************************************** * RECOMMENDATION: * **************************************************************** If a large number of concurrent requests run immediately after an application is started, there is a chance that a java.util.ConcurrentModificationException will occur that will fail all future requests until the application is restarted. Here is an example of the stack trace for this issue, which can be seen in messages.log: Caused by: java.util.ConcurrentModificationException at java.util.ArrayList$Itr.checkForComodification(ArrayList.java:91 2) at java.util.ArrayList$Itr.next(ArrayList.java:862) at com.ibm.ws.webcontainer.util.MetaInfResourcesFileUtils.(MetaInfR esourcesFileUtils.java:81) at com.ibm.ws.webcontainer.util.DocumentRootUtils.getMetaInfRes(Doc umentRootUtils.java:492) at com.ibm.ws.webcontainer.util.DocumentRootUtils.handleDocumentRoo ts(DocumentRootUtils.java:204) at com.ibm.ws.webcontainer.util.DocumentRootUtils.handleDocumentRoo ts(DocumentRootUtils.java:171) at com.ibm.ws.webcontainer.osgi.webapp.WebApp.getResourceAsStream(W ebApp.java:544) at com.ibm.wsspi.webcontainer.facade.ServletContextFacade.getResour ceAsStream(ServletContextFacade.java:158)
Problem conclusion
The web container was modified to correctly handle the resources list that led to the ConcurrentModificationException. The fix for this APAR is currently targeted for inclusion in fix pack 19.0.0.1. Please refer to the Recommended Updates page for delivery information: http://www.ibm.com/support/docview.wss?rs=180&uid=swg27004980
Temporary fix
Restart the application.
Comments
APAR Information
APAR number
PH05787
Reported component name
WAS LIBERTY COR
Reported component ID
5725L2900
Reported release
855
Status
CLOSED PER
PE
NoPE
HIPER
NoHIPER
Special Attention
NoSpecatt / Xsystem
Submitted date
2018-11-27
Closed date
2019-02-05
Last modified date
2019-02-05
APAR is sysrouted FROM one or more of the following:
APAR is sysrouted TO one or more of the following:
Fix information
Fixed component name
WAS LIBERTY COR
Fixed component ID
5725L2900
Applicable component levels
R855 PSY
UP
Document Information
Modified date:
17 October 2021