Fixes are available
APAR status
Closed as program error.
Error description
WMQ 7.0.1.8 Java. High CPU usage noticed for PoolScavenger thread or PoolScavenger thread appears to be hung in Javacore.
Local fix
Restart JVM allows for temporary relief.
Problem summary
**************************************************************** USERS AFFECTED: This issue effects uses of the WebSphere MQ classes for Java V7.0, V7.1 and V7.5 who are making use of Connection Pooling. Platforms affected: All Distributed (iSeries, all Unix and Windows) +Java +Java zOS **************************************************************** PROBLEM SUMMARY: The PoolScavenger thread controls when an MQ Connection is to be removed from the MQ Connection Pool either due to connection expiry or that the limit for the connection pool has been reached. When the PoolScavenger thread detected that a connection should be destroyed it attempted to cleanup the connection, but the connection was incorrectly marked as being in use by an application. This then caused the PoolScavenger thread to fail to remove the connection which resulted in the PoolScavenger thread looping in a tight loop as it attempted to remove that connection. A Javacore of the system showed that the PoolScavenger thread was constantly running rather than in a wait state. High CPU was also seen with this thread.
Problem conclusion
This APAR solves the issue by making sure that the connection is not marked as in use when it is added to the MQ Connection Pool. --------------------------------------------------------------- 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
IV32346
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
2012-11-20
Closed date
2012-11-30
Last modified date
2012-11-30
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
WMQ AIX V7
Fixed component ID
5724H7221
Applicable component levels
R701 PSY
UP
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Document Information
Modified date:
01 October 2021