APAR status
Closed as program error.
Error description
IBM Websphere Application Server Enterprise Process
Choreographer processes that are interruptible that use
JMS activities extensively experience a problem in which
the Connection pools get short on connections after a short
period of time.
The following is a scenario that demonstrates this problem:
(WPC stands for WebSphere Process Choreographer)
Each invocation of a JMS backend via WSIF is separated by
WPC into 2 transactions. In the first transaction, a WSIF
service, port and operation is created and then the
executeRequestResponseAsync() method is invoked on this
operation. Then the WSIFOperation is serialized into the
database. The operation has a reference to the port as
datamember, therefore the port is also serialized and
stored in the database. Then the port is closed, and
the first transaction ends.
In the second transaction, WPC's MDB receives the reply
message from the backend. It identifies (using the
correlation ID of this message) the associated WSIFOperation
in the database and deserializes this WSIFOperation. Since
the operation containes a reference to the port, the
associated port is also deserialized. WPC then calls the
processAsyncResponse() function on this operation, which
under the covers opens a JMS connection through the port,
although the message has already been received. The opening
of a new connection not only wastes connection resources,
it is also a very expensive operation in terms of
performance and there is no real need for this.
Suggested solution: WSIF has to refrain from opening a JMS
connection in the WSIFOperation.processAsyncResponse() function.
Summary of end-user symptoms:
WebSphere Process Choreographer processing stops with java
exceptions because there are no more free connections
available. The following messages can appear:
FreePool E J2CA0045E: Connection not available while invoking
method queueRequest for resource JMS$BPECF.
ConnectionMan E J2CA0020E: The Connection Pool Manager could not
allocate a Managed Connection: com.ibm.websphere.ce.j2c.Connec
tionWaitTimeoutException: Connection not available, Timed out
waiting.
.
This problem may also cause WTRN0075W: The transaction log file
is full. It may also cause a
com.ibm.ejs.jts.tranLog.tranLogFullException to be logged
in the ffdc files.
Local fix Problem summary
****************************************************************
* USERS AFFECTED: Users of WebSphere Application Server *
* Enterprise Process Choreographer processes *
* that are interruptible and use JMS *
* activities. *
* Users of WSIF that use Web Services via *
* JMS and asynchronous send/receive, if *
* WSIFOperation used to send and process the *
* response is serialized between sending and *
* processing the response. *
****************************************************************
* PROBLEM DESCRIPTION: IBM Websphere Application Server *
* Enterprise Process Choreographer *
* processes that are interruptible that *
* use JMS activities extensively *
* experience a problem in which the *
* Connection pools get short on *
* connections after a short period of *
* time. *
* WebSphere Process Choreographer *
* processing stops with java *
* exceptions because there are no more *
* free connections available. The *
* following messages can appear: *
* FreePool E J2CA0045E: Connection not *
* available while invoking method *
* queueRequest for resource *
* JMS$BPECF. *
* ConnectionMan E J2CA0020E: The *
* Connection Pool Manager could not *
* allocate a Managed Connection: *
* com.ibm.websphere.ce.j2c.Connection *
* WaitTimeoutException: Connection not *
* available, Timed out waiting. *
* *
* The above errors can occur for users *
* of WSIF that use Web Services via JMS *
* and asynchronous send/receive, if *
* WSIFOperation used to send and *
* process the response is serialized *
* between sending and processing the *
* response. If many such send/receives *
* occur in a short timescale (under *
* stress) the errors can occur. *
****************************************************************
* RECOMMENDATION: All WSIF users should apply the fix. *
****************************************************************
WSIF creates JMS Connections when a WSIF Operation is
deserialized and then used to process an asynchronous JMS
response.
Problem conclusion
It is recommended that customers encountering this problem
should install WebSphere Application Server V5.1.0 with
cumulative fix 1, WebSphere Application Server V5.0.2 with
cumulative fix 4.
Alternatively, the fix to this problem is also available as
an iFix to WebSphere Application Server V5.0.2.
Temporary fix Comments
APAR information |
APAR number |
PQ82698 |
Reported component name |
WAS BASE 5.0 |
Reported component ID |
5630A3600 |
Reported release |
00W |
Status |
CLOSED PER |
PE |
NoPE |
HIPER |
NoHIPER |
Special Attention |
NoSpecatt |
Submitted date |
2003-12-30 |
Closed date |
2004-01-29 |
Last modified date |
2004-01-29 |
APAR is sysrouted FROM one or more of the following:
APAR is sysrouted TO one or more of the following:
Modules/Macros
Publications Referenced
Applicable component levels |
R003 PSY |
UP |
R00A PSY |
UP |
R00H PSY |
UP |
R00I PSY |
UP |
R00P PSY |
UP |
R00S PSY |
UP |
R00W PSY |
UP |
R103 PSY |
UP |
R10A PSY |
UP |
R10H PSY |
UP |
R10I PSY |
UP |
R10P PSY |
UP |
R10S PSY |
UP |
R10W PSY |
UP |
|