What's changed in IBM MQ 9.2.0 Fix Pack 35

IBM® MQ 9.2.0 Fix Pack 35 includes resource changes.

Performance monitoring enhancements

From IBM MQ 9.2.0 Fix Pack 35, you can use the mqperfck command to generate an HTML report containing performance metrics for specified queues or channels over a set time period. The report shows key system and queue manager metrics such as CPU load and IO rate, as well as metrics for the object(s) under observation such as lock contention, MQI counts, selector and match-option mismatches, and network time. The report allows customers and IBM Support to review and compare workload between normal and problematic time periods or performant and non-performant environments. It is intended to gain insight into workload patterns during times of performance sensitivity without the need to capture IBM MQ trace. For more information, see mqperfck (MQ performance check) and Metrics published on the system topics.

You can suppress the publication of the new statistics and their metadata by setting the AMQ_NO_MQPERFCK_STATS environment variable to any value before starting the queue manager.

Changes to allow IBM MQ Java client properties com.ibm.mq.cfg.TCP.ClntRcvBuffSize and com.ibm.mq.cfg.TCP.ClntSndBuffSize to be set to zero

From IBM MQ 9.2.0 Fix Pack 35, if the value of either the com.ibm.mq.cfg.TCP.ClntRcvBuffSize or the com.ibm.mq.cfg.TCP.ClntSndBuffSize property is set as zero for an IBM MQ Java client, the Java Message Queuing Interface (JMQI) uses the buffer size provided by the network layer. This resolves a previous issue where setting the properties to zero would incorrectly result in the JMQI using TCP/IP send and/or receive buffers of size 32K when communicating with a queue manager. For more information, see TCP stanza of the client configuration file.

New DNSResolutionOrder attribute of TCP stanza

From IBM MQ 9.2.0 Fix Pack 35, the DNSResolutionOrder attribute specifies the order in which IBM MQ looks up host names in mixed IPv6 and IPv4 environments. If the AMQ_NO_IPV6 environment variable is set, IBM MQ acts as if DNSResolutionOrder=IPV4 is set, no matter what value is configured.

For more information, see TCP stanza of the qm.ini file and TCP stanza of the client configuration file.