APAR status
Closed as program error.
Error description
When you configured memory-to-memory session replication in
WebSphere V5 Application server, under the load AppServer JVM
may get into a hung state. If it happens, you can observe many
Servlet Engine HTTP Transport threads in javacore with this
java stack (javacore was taken from a hung JVM/AppServer):
.
"Servlet.Engine.Transports : 33" (TID:0x1091EC38,
sys_thread_t:0x454255F0, state:R, native ID:0xE44) prio=5
at java.util.HashMap.put(HashMap.java(Compiled Code))
at
com.ibm.ws.webcontainer.httpsession.DRSBackedHashtable.readFromE
xternal(DRSBackedHashtable.java(Compiled Code))
at
com.ibm.ws.webcontainer.httpsession.BackedHashtable.retrieveSess
ion(BackedHashtable.java(Compiled Code))
at
com.ibm.ws.webcontainer.httpsession.BackedHashtable.getSession(B
ackedHashtable.java(Compiled Code))
at
com.ibm.ws.webcontainer.httpsession.BackedHashtable.get(BackedHa
shtable.java(Compiled Code))
at
com.ibm.ws.webcontainer.httpsession.SessionContext.tableGet(Sess
ionContext.java(Compiled Code))
at
at
com.ibm.ws.webcontainer.httpsession.SessionContext.findSession(S
essionContext.java(Compiled Code))
at
com.ibm.ws.webcontainer.httpsession.SessionContext.getIHttpSessi
on(SessionContext.java(Compiled Code))
at
com.ibm.ws.webcontainer.httpsession.SessionContext.getIHttpSessi
on(SessionContext.java(Compiled Code))
at
at
com.ibm.ws.webcontainer.webapp.WebAppDispatcherContext.getSessio
n(WebAppDispatcherContext.java(Compiled Code))
at
com.ibm.ws.webcontainer.srt.SRTServletRequestContext.getSession(
SRTServletRequestContext.java(Compiled Code))
at
com.ibm.ws.webcontainer.srt.SRTServletRequest.getSession(SRTServ
letRequest.java(Compiled Code))
at
com.ibm.ws.cscope.CScopeWebInvocationCollaborator.preInvoke(CSco
peWebInvocationCollaborator.java(Compiled Code))
at
com.ibm.ws.webcontainer.webapp.WebAppRequestDispatcher.dispatch(
WebAppRequestDispatcher.java(Compiled Code))
at
com.ibm.ws.webcontainer.webapp.WebAppRequestDispatcher.forward(W
ebAppRequestDispatcher.java(Compiled Code))
at
com.ibm.ws.webcontainer.srt.WebAppInvoker.doForward(WebAppInvoke
r.java(Compiled Code))
at
com.ibm.ws.webcontainer.srt.WebAppInvoker.handleInvocationHook(W
ebAppInvoker.java(Compiled Code))
at
com.ibm.ws.webcontainer.cache.invocation.CachedInvocation.handle
Invocation(CachedInvocation.java(Compiled Code))
at
com.ibm.ws.webcontainer.cache.invocation.CacheableInvocationCon
text.invoke(CacheableInvocationContext.java(Compiled Code))
at
com.ibm.ws.webcontainer.srp.ServletRequestProcessor.dispatchByU
RI(ServletRequestProcessor.java(Compiled Code))
at
com.ibm.ws.webcontainer.oselistener.OSEListenerDispatcher.servi
ce(OSEListener.java(Compiled Code))
at
com.ibm.ws.webcontainer.http.HttpConnection.handleRequest(HttpCo
nnection.java(Compiled Code))
at
com.ibm.ws.http.HttpConnection.readAndHandleRequest(HttpConnecti
on.java(Compiled Code))
at com.ibm.ws.http.HttpConnection.run(HttpConnection.java:458)
.
This JVM/AppServer hang problem in WebSphere session code
was reported in WebSphere V5.1.1.7 release with Portal V5.1.0.1
application.
Local fix
N/A.
Problem summary
****************************************************************
* USERS AFFECTED: WebSphere Application Server version 5 *
* users who use memory to memory session *
* persistence. *
****************************************************************
* PROBLEM DESCRIPTION: When using memory to memory session *
* persistence, the application server *
* might hang when multiple threads are *
* accessing the session. *
****************************************************************
* RECOMMENDATION: *
****************************************************************
The code that stores a list of cached session ids was not
synchronized properly. When multiple threads access the
list, they might run into a hung state when trying to
update them at the same time.
Problem conclusion
The session code has been properly synchronized to support
multiple thread accessing them at the same time.
The fix for this APAR is currently targeted for inclusion in
fixpack 5.0.2.16 and 5.1.1.9. Please refer to the Recommended
Updates page for delivery information:
http://www.ibm.com/support/docview.wss?rs=180&uid=swg27004980
Temporary fix Comments
APAR information |
APAR number |
PK16249 |
Reported component name |
WAS NETWRK DEPL |
Reported component ID |
5630A3601 |
Reported release |
10W |
Status |
CLOSED PER |
PE |
NoPE |
HIPER |
NoHIPER |
Special Attention |
NoSpecatt |
Submitted date |
2005-12-05 |
Closed date |
2005-12-14 |
Last modified date |
2005-12-14 |
APAR is sysrouted FROM one or more of the following:
APAR is sysrouted TO one or more of the following:
Modules/Macros
Publications Referenced
|
Fix information |
Fixed component name |
WAS NETWRK DEPL |
Fixed component ID |
5630A3601 |
Applicable component levels |
R00A PSY |
UP |
R00H PSY |
UP |
R00I PSY |
UP |
R00P PSY |
UP |
R00S PSY |
UP |
R00W PSY |
UP |
R10A PSY |
UP |
R10H PSY |
UP |
R10I PSY |
UP |
R10P PSY |
UP |
R10S PSY |
UP |
R10W PSY |
UP |
|