PK76291: Runtime problems using the WebSphere MQ messaging provider in WebSphere Application Server for z/OS

Fixes are available

APAR status

Closed as program error.

Error description

Errors thrown at runtime when using the WebSphere MQ Resource
Adapter in WebSphere Application Server for z/OS

Local fix

Problem summary

****************************************************************
* USERS AFFECTED:  Users of WebSphere Application Server for   *
*                  z/OS V7 using WebSphere MQ as a messaging   *
*                  provider.                                   *
****************************************************************
* PROBLEM DESCRIPTION: Issues may be experienced at runtime    *
*                      when using WebSphere MQ as a            *
*                      messaging provider.                     *
****************************************************************
* RECOMMENDATION:                                              *
****************************************************************
Message listener ports make use of a pool of server sessions.
Initially this pool is empty. When work comes in server
sessions are created to satisfy the work and are then put into
the pool. If the pool is configured to support multiple server
sessions - which is not the case by default - it is possible
for multiple server sessions to be in the process of being
created at the same time. Currently server sessions are
created in a serial manner. If the resources used by the
server sessMessage listener ports make use of a pool of server
sessions.
Initially this pool is empty. When work comes in server
sessions are created to satisfy the work and are then put into
the pool. If the pool is configured to support multiple server
sessions - which is not the case by default - it is possible
for multiple server sessions to be in the process of being
created at the same time. Currently server sessions are
created in a serial manner. If the resources used by the
server session such as a JMS session take a long time to set
up, the z/WLM requests which caused the server sessions to be
created will time out. If a z/WLM request times out it results
in the shutdown of the servant region to which the request was
dispatched.

The solution to this problem is to not serialize the creation
of server sessions.

This problem will give rise to lines like the following in the
control region:

13.14.28 STC18852  BBOO0327I MDB Plan "A" REQUEST TIMEOUT:  972
    972
(06CB):(FFF6AD9E):(0002001D):(009BA020):(STC18855):(2008/09/30
    972             12:12:45.345177):(2008/09/30
12:12:45.346700):(2008/09/30
    972
12:12:45.347489):(mdbclass):(mdbrequest):(Local to this
    972             Server):():():(WMQEXTLP)
 13.14.28 STC18852  BBOO0232W A request for Class Name
'mdbclass' and Method Name  973
    973             'mdbrequest', from Local to this Server,
has timed out.  The servant
    973             process associated with the request will
be terminated. Request
    973             Id(FFF6AD9E)
 13.14.28 STC18852  BBOO0303I ADDITIONAL INFORMATION FOR MDB
REQUEST TIMEOUT: WMQEXTLP
 13.14.38 STC18852  BBOO0327I MDB Plan "A" REQUEST TIMEOUT:  978
    978
(06CB):(FFF6AD98):(0002001D):(009C5188):(STC18855):(2008/09/30
 13.14.38 STC18852  BBOO0327I MDB Plan "A" REQUEST TIMEOUT:  979
    978             12:12:52.349835):(2008/09/30
12:12:52.349943):(2008/09/30
    979
(06CB):(FFF6AD9B):(0002001D):(009BAA60):(STC18855):(2008/09/30
    978
12:12:52.351211):(mdbclass):(mdbrequest):(Local to this
    978             Server):():():(WMQEXTLP)
    979             12:12:47.995545):(2008/09/30
12:12:47.995684):(2008/09/30
    979
12:12:47.995896):(mdbclass):(mdbrequest):(Local to this
    979             Server):():():(WMQEXTLP)
 13.14.38 STC18852  BBOO0232W A request for Class Name
'mdbclass' and Method Name  980
    980             'mdbrequest', from Local to this Server,
has timed out.  The servant
    980             process associated with the request will
be terminated. Request
    980             Id(FFF6AD98)
 13.14.38 STC18852  BBOO0232W A request for Class Name
'mdbclass' and Method Name  981
    981             'mdbrequest', from Local to this Server,
has timed out.  The servant
    981             process associated with the request will
be terminated. Request
    981             Id(FFF6AD9B)
 13.14.38 STC18852  BBOO0303I ADDITIONAL INFORMATION FOR MDB
REQUEST TIMEOUT: WMQEXTLP
 13.14.38 STC18852  BBOO0303I ADDITIONAL INFORMATION FOR MDB
REQUEST TIMEOUT: WMQEXTLP

and the servant region abending.


When using WMQ messaging provider activation specification on
z/OS work is passed from the control region adjunct process to
a specific servant region by z/OS work load management
(z/WLM). When this work is dispatched into the servant region
it is assocated with a particular transaction class by z/WLM.
This work is then passed into a thread pool and a thread
switch occurs which potentially results in the work being done
under a different transaction class thus WMQ messaging
provider activation specification WLM classification doesn't
work properly.

This issue is fixed by removing the thread switch and
performing the work under the correct transaction class.


The following exception may be seen when stopping MDBs that
use message listener ports in WebSphere Application Server for
z/OS with the WebSphere MQ messaging provider, this problem
does not have any functional effect:

javax.jms.IllegalStateException: Session closed
 at
com.ibm.ejs.jms.JMSSessionHandle.getOpenSession(JMSSessionHandle
.java:1235)
 at
com.ibm.ejs.jms.JMSSessionHandle.getOpenUnifiedSession(JMSSessio
nHandle.java:1272)
 at
com.ibm.ejs.jms.JMSSessionHandle.getTransacted(JMSSessionHandle.
java:604)
 at
com.ibm.ejs.jms.listener.WS390ServerSession.onMessage(WS390Serve
rSession.java:469)
 at
com.ibm.ejs.jms.listener.ServerSession.dispatch(ServerSession.ja
va:639)
 at sun.reflect.GeneratedMethodAccessor43.invoke(Unknown Source)
 at
sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethod
AccessorImpl.java:37)
 at java.lang.reflect.Method.invoke(Method.java:599)
 at
com.ibm.ejs.jms.listener.ServerSessionDispatcher.dispatch(Server
SessionDispatcher.java:37)
 at
com.ibm.ejs.container.MDBWrapper.onMessage(MDBWrapper.java:96)
 at
com.ibm.ejs.container.MDBWrapper.onMessage(MDBWrapper.java:132)
 at
com.ibm.ejs.jms.listener.WS390ServerSession.runMR(WS390ServerSes
sion.java:210)
 at
com.ibm.ejs.jms.listener.MDBCppUtilitiesInterfaceImpl.onMessageR
eference(MDBCppUtilitiesInterfaceImpl.java:253)
 at
com.ibm.ws390.mdb.MDBCppUtilities.onMessageReference(MDBCppUtili
ties.java:153)
 at
com.ibm.ws390.orb.CommonBridge.nativeRunApplicationThread(Native
 Method)
 at
com.ibm.ws390.orb.CommonBridge.runApplicationThread(CommonBridge
.java:460)
 at
com.ibm.ws.util.ThreadPool$ZOSWorker.run(ThreadPool.java:1724)


An MDB application on WebSphere Application Server for z/OS
which uses an WebSphere MQ messaging provider activation
specification to listen to a topic fails to start with the
following exception:
om.ibm.ws.wmqra.utils.MalformedDestinationUriException:
topic://MQTopic?XMSC_WMQ_BROKER_PUBQ=SYSTEM.BROKER.DEFAULT.STREA
M
  at
com.ibm.ws.wmqra.utils.WMQObjectNameUtils.getQueueNameFromUri(WM
QObjectNameUtils.java:248)
  at
com.ibm.ws.wmqra.helper.WASRuntimeHelper.getCraMessageReferenceH
andler(WASRuntimeHelper.java:485)
  at
com.ibm.mq.connector.inbound.MessageEndpointDeployment.createCon
nectionConsumer(MessageEndpointDeployment.java:346)
  at
com.ibm.mq.connector.inbound.MessageEndpointDeployment.start(Mes
sageEndpointDeployment.java:228)

Problem conclusion

This APAR resolves the above runtime issues that can be
experienced when using WebSphere MQ as a messaging provider.

Temporary fix

Comments

APAR Information

APAR number
PK76291
Reported component name
PLAT MSG COM
Reported component ID
620800101
Reported release
300
Status
CLOSED PER
PE
NoPE
HIPER
NoHIPER
Special Attention
NoSpecatt
Submitted date
2008-11-24
Closed date
2009-03-02
Last modified date
2009-03-02

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
PLAT MSG COM
Fixed component ID
620800101

Applicable component levels

R300 PSY
UP

[{"Business Unit":{"code":"BU053","label":"Cloud & Data Platform"},"Product":{"code":"SSEQTP","label":"WebSphere Application Server"},"Platform":[{"code":"PF025","label":"Platform Independent"}],"Version":"7.0","Line of Business":{"code":"LOB45","label":"Automation"}}]

Document Information

Modified date:
23 October 2021

Tips

PK76291: Runtime problems using the WebSphere MQ messaging provider in WebSphere Application Server for z/OS

Fixes are available

Subscribe

APAR status

Closed as program error.

Error description

Local fix

Problem summary

Problem conclusion

Temporary fix

Comments

APAR Information

APAR number

Reported component name

Reported component ID

Reported release

Status

PE

HIPER

Special Attention

Submitted date

Closed date

Last modified date

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

Fixed component ID

Applicable component levels

R300 PSY

Document Information

Share your feedback

Need support?