Session locking resulting in Endless Loop

[Former Member]

Hi guys,

While testing Family Members iView, everything is working fine except when I click on the "delete" button to delete subtype, it causes the iview to loop forever until a "Page cannot be displayed" error is displayed after a very very long time. However, when i tested it in another server, it is working fine. Does anyone hv any idea?

Below is the exception caught in the log file:

com.sap.tc.webdynpro.sessionmanagement#sap.com/tc_wddispwda#com.sap.tc.webdynpro.sessionmanagement.ExceptionHandler.handleThrowable#A_ZM#637##vq2c1.ehrpm.com_PD1_17586350#A_ZHENMIN#4b212f7091bf11dd9b4c00145e5a3f2a#SAPEngine_Application_Thread[impl:3]_25##0#0#Error#1#/System/UserInterface#Java###Exception occured during processing of Web Dynpro application . The causing exception is nested.

[EXCEPTION]

#2#sap.com/ess_sgfam/Per_Family_SG#com.sap.tc.webdynpro.services.session.LockException: Thread SAPEngine_Application_Thread[impl:3]_25 failed to acquire exclusive lock on client session ClientSession(id=(vq2c1_PD1_01)ID0324092450DB10117000369574636226End_1014127312). Existing locks: LockingManager(ThreadName:SAPEngine_Application_Thread[impl:3]_25, exclusive client session lock: ClientSessionLock(SAPEngine_Application_Thread[impl:3]_23), shared client session locks: ClientSessionSharedLockManager([]), app session locks: ApplicationSessionLockManager([]), current request: sap.com/ess_sgfam/Per_Family_SG).Hint: Take a thread dump of the server node to find the blocking thread that causes the problem.

at com.sap.tc.webdynpro.clientserver.session.ClientSession$LockingManager.lock(ClientSession.java:1511)

at com.sap.tc.webdynpro.clientserver.session.ClientSession.doProcessing(ClientSession.java:233)

at com.sap.tc.webdynpro.clientserver.session.RequestManager.doProcessing(RequestManager.java:149)

at com.sap.tc.webdynpro.serverimpl.defaultimpl.DispatcherServlet.doContent(DispatcherServlet.java:62)

at com.sap.tc.webdynpro.serverimpl.defaultimpl.DispatcherServlet.doGet(DispatcherServlet.java:46)

at javax.servlet.http.HttpServlet.service(HttpServlet.java:740)

at javax.servlet.http.HttpServlet.service(HttpServlet.java:853)

at com.sap.engine.services.servlets_jsp.server.HttpHandlerImpl.runServlet(HttpHandlerImpl.java:401)

at com.sap.engine.services.servlets_jsp.server.HttpHandlerImpl.handleRequest(HttpHandlerImpl.java:266)

at com.sap.engine.services.httpserver.server.RequestAnalizer.startServlet(RequestAnalizer.java:386)

at com.sap.engine.services.httpserver.server.RequestAnalizer.startServlet(RequestAnalizer.java:364)

at com.sap.engine.services.httpserver.server.RequestAnalizer.invokeWebContainer(RequestAnalizer.java:1039)

at com.sap.engine.services.httpserver.server.RequestAnalizer.handle(RequestAnalizer.java:265)

at com.sap.engine.services.httpserver.server.Client.handle(Client.java:95)

at com.sap.engine.services.httpserver.server.Processor.request(Processor.java:175)

at com.sap.engine.core.service630.context.cluster.session.ApplicationSessionMessageListener.process(ApplicationSessionMessageListener.java:33)

at com.sap.engine.core.cluster.impl6.session.MessageRunner.run(MessageRunner.java:41)

at com.sap.engine.core.thread.impl3.ActionObject.run(ActionObject.java:37)

at java.security.AccessController.doPrivileged(Native Method)

at com.sap.engine.core.thread.impl3.SingleThread.execute(SingleThread.java:102)

at com.sap.engine.core.thread.impl3.SingleThread.run(SingleThread.java:172)

[Former Member]

Hi Koti,

Thanks for the help. I tried to take a thread dump but unfortunately, we have dual stack (both Java n ABAP) installed on the same server. Thus, the tip in the note is inapplicable in our case to extract the dump. Do you know of any other ways to extract the dump? Thank you.

[Former Member]

Hi Zhenmin,

Check the below sap note which address your concern.

Note 1234847 - Analysing WebDynpro session LockException

Koti Reddy

[Former Member]

Anybody can provide any helpful hints or any logs I can check? Any help would be great! Thanks!