Fixes are available
APAR status
Closed as program error.
Error description
Higher than expected CPU usage is observed on z/OS, when WebSphere Application Server is performing transactional recovery of Activation specifications. JVM analysis may also show an unexpected increase in object allocations. The tracebacks of these allocatiosns show the following stack: at java/lang/StringBuffer.ensureCapacityImpl(I) (StringBuffer.java:33) at java/lang/StringBuffer.append(Ljava/lang/String;) at com/ibm/msg/client/commonservices/trace/ Trace.createFFSTString(Ljav at com/ibm/msg/client/commonservices/trace/ Trace.ffstInternal(Ljava/la at com/ibm/msg/client/commonservices/trace/ Trace.ffst(Ljava/lang/Objec at com/ibm/msg/client/wmq/common/internal/ WMQTraceHandler.ffst(Ljava/l at com/ibm/msg/client/wmq/common/internal/ WMQTraceHandler.ffst(Ljava/l at com/ibm/mq/jmqi/JmqiXAResource.<init> (Lcom/ibm/mq/jmqi/JmqiEnvironm at com/ibm/mq/jmqi/JmqiXAResource.getInstance (Lcom/ibm/mq/jmqi/JmqiEnv at com/ibm/mq/jmqi/JmqiEnvironment.newJmqiXAResource (Lcom/ibm/mq/jmqi/ at com/ibm/msg/client/wmq/internal/WMQXASession.<init> (Lcom/ibm/msg/cl at com/ibm/msg/client/wmq/internal/WMQXAConnection. createXASession(Lco at com/ibm/msg/client/jms/internal/JmsXAConnectionImpl. createXASession at com/ibm/mq/jms/MQXAConnection.createXASession() Ljavax/jms/XASession at com/ibm/mq/connector/ResourceAdapterImpl. getXAResources(Ljavax/res at com/ibm/ws/tx/jta/ASXAResourceFactoryImpl. getXAResource(Lcom/ibm/ws at com/ibm/ws/Transaction/JTA/XARecoveryData. getXARminst()Lcom/ibm/w at com/ibm/ws/Transaction/JTA/XARecoveryData.recover at com/ibm/ws390/tx/XARecoveryAgentImpl. rollbackUnknownTransactions at com/ibm/ws390/tx/XARecoveryAgentImpl $XARecoveryAgentThread.run() Application server traces also show the following error: Trace: 2012/07/18 21:57:03.288 01 t=8BB548 c=UNK key=P8 ThreadId: 00000046 FunctionName: JmqiXAResource SourceId: JmqiXAResource Category: FINE ExtendedMessage: (JmqiXAResource) Tracing exception: javax.transaction.xa.XAException: The method 'xa_open' has failed because of an internal error. at java.lang.Throwable.<init>(Throwable.java:67) at com.ibm.mq.jmqi.JmqiXAResource.<init> (JmqiXAResource.java:137) at com.ibm.mq.jmqi.JmqiXAResource.getInstance (JmqiXAResource.java:104) at com.ibm.mq.jmqi.JmqiEnvironment.newJmqiXAResource (JmqiEnvironment.ja at com.ibm.msg.client.wmq.internal.WMQXASession. <init>(WMQXASession.jav at com.ibm.msg.client.wmq.internal.WMQXAConnection. createXASession(WMQX at com.ibm.msg.client.jms.internal.JmsXAConnectionImpl. createXASession( at com.ibm.mq.jms.MQXAConnection.createXASession (MQXAConnection.java:83 at com.ibm.mq.connector.ResourceAdapterImpl. getXAResources(ResourceAdap at com.ibm.ws.tx.jta.ASXAResourceFactoryImpl. getXAResource(ASXAResource at com.ibm.ws.Transaction.JTA.XARecoveryData. getXARminst(XARecoveryData at com.ibm.ws.Transaction.JTA.XARecoveryData. recover(XARecoveryData.jav at com.ibm.ws390.tx.XARecoveryAgentImpl. rollbackUnknownTransactions(XAR at com.ibm.ws390.tx.XARecoveryAgentImpl $XARecoveryAgentThread.run(XARec . ADDITIONAL SYMPTOMS: If WSAS is started in recovery mode, and BINDING_THEN_CLIENT is configured for an activation specification that is connecting in BINDING mode, the following linked exception occurs: Caused by: com.ibm.mq.jmqi.JmqiException: CC=2;RC=2495;AMQ8568: The native JNI library 'mqjrrs64' was not found. [3=mqjrrs64] . AMQ8568 2495 MQRC_MODULE_NOT_FOUND mqjrrs64 not found
Local fix
Local Fix￘ .
Problem summary
**************************************************************** USERS AFFECTED: This issue affects users of WebSphere Application Server on z/ OS who are using the WebSphere MQ Messaging Provider to communicate with a WebSphere MQ queue manager, and who have configured one or more Activation Specifications to use "BINDINGS_THEN_CLIENT" connection mode. Platforms affected: All Distributed (iSeries, all Unix and Windows) +Java +Java zOS **************************************************************** PROBLEM SUMMARY: When running WebSphere Application Server and the WebSphere MQ Messaging Provider on z/OS, shared memory bindings ("bindings mode") connections to the WebSphere MQ Queue Manager rely on the transactional functionality provided by the RRS component of z/OS, instead of XA transactions which are used by other WebSphere MQ connection modes. In order to remain compatible with Java EE environments, the WebSphere MQ Messaging Provider continues to accept XA calls from the Transaction Manager for z/OS bindings mode connections. In the case of transactional recovery, the WebSphere MQ Messaging Provider is asked by the Application Server to return a list of XAResource objects to be recovered. In this case, the WebSphere MQ Messaging Provider returned a dummy XAResource object for each Activation Specification that was using a bindings mode connection, as there was no XA work to do. The issue occurred when the Activation Specifications were configured to use a bindings then client connection mode. In this case, the WebSphere MQ Messaging Provider did not return a dummy resource, and attempted to create an XA connection to the queue manager to perform transactional recovery. The WebSphere MQ Messaging Provider incorrectly opened a bindings mode connection to do this, leading to the exception seen in the trace above, as a bindings connection on z/OS cannot accept XA API calls.
Problem conclusion
The XA recovery mechanism in the WebSphere MQ Messaging provider has been modified so that when performing transactional recovery of an Activation Specification that is configured to use "bindings then client" connection mode, no attempt is made to flow XA API calls to the queue manager using a bindings connection. --------------------------------------------------------------- The fix is targeted for delivery in the following PTFs: v7.0 Platform Fix Pack 7.0.1.10 -------- -------------------- Windows U200352 AIX U853055 HP-UX (PA-RISC) U853082 HP-UX (Itanium) U853087 Solaris (SPARC) U853083 Solaris (x86-64) U853089 iSeries 7.0.1.10 Linux (x86) U853084 Linux (x86-64) U853088 Linux (zSeries) U853085 Linux (Power) U853086 zOS 7.0.1.10 v7.1 Platform Fix Pack 7.1.0.3 -------- -------------------- Windows 7.1.0.3 AIX 7.1.0.3 HP-UX (Itanium) 7.1.0.3 Solaris (SPARC) 7.1.0.3 Solaris (x86-64) 7.1.0.3 iSeries 7.1.0.3 Linux (x86) 7.1.0.3 Linux (x86-64) 7.1.0.3 Linux (zSeries) 7.1.0.3 Linux (Power) 7.1.0.3 zOS 7.1.0.3 Platform v7.5 -------- -------------------- Multiplatforms 7.5.0.1 The latest available maintenance can be obtained from 'WebSphere MQ Recommended Fixes' http://www-1.ibm.com/support/docview.wss?rs=171&uid=swg27006037 If the maintenance level is not yet available information on its planned availability can be found in 'WebSphere MQ Planned Maintenance Release Dates' http://www-1.ibm.com/support/docview.wss?rs=171&uid=swg27006309 ---------------------------------------------------------------
Temporary fix
Comments
APAR Information
APAR number
IV25039
Reported component name
WMQ AIX V7
Reported component ID
5724H7221
Reported release
701
Status
CLOSED PER
PE
NoPE
HIPER
NoHIPER
Special Attention
NoSpecatt
Submitted date
2012-07-23
Closed date
2012-10-19
Last modified date
2014-02-07
APAR is sysrouted FROM one or more of the following:
APAR is sysrouted TO one or more of the following:
PM69659 PM90856
Fix information
Fixed component name
WMQ AIX V7
Fixed component ID
5724H7221
Applicable component levels
R701 PSY
UP
[{"Line of Business":{"code":"LOB45","label":"Automation"},"Business Unit":{"code":"BU053","label":"Cloud & Data Platform"},"Product":{"code":"SSFKSJ","label":"WebSphere MQ"},"Platform":[{"code":"PF025","label":"Platform Independent"}],"Version":"7.0.1"}]
Document Information
Modified date:
03 October 2021