ClusterSenderStatistics (MQLONG)
Because cluster sender channels can be automatically defined from the definition of CLUSRCVR in the repository, we cannot alter the setting of the STATCHL attribute for these auto-defined cluster sender channels using ALTER channel. For these channels the decision of whether to collect online monitoring data is based on the setting of this queue manager attribute.
The value is one of the following:
- MQMON_Q_MGR
- Statistics data collection for auto-defined cluster sender channels is based on the value of the queue manager attribute STATCHL. This is the default value.
- MQMON_OFF
- Switch off statistics data collection for auto-defined cluster sender channels.
- MQMON_LOW
- Enable statistics data collection for auto-defined cluster sender channels with a low ratio of data collection.
- MQMON_MEDIUM
- Enable statistics data collection for auto-defined cluster sender channels with a moderate ratio of data collection.
- MQMON_HIGH
- Enable statistics data collection for auto-defined cluster sender channels with a high ratio of data collection.
For most systems we recommend MEDIUM. However, for an auto-defined cluster sender channel that processes a high volume of messages each second, you might want to reduce the sampling level by selecting LOW. Also, for a channel that processes only a few messages, and for which the most current information is important, you might want to select HIGH.
On z/OS systems, enabling this parameter simply turns on statistics data collection, regardless of the value you select. Specifying LOW, MEDIUM, or HIGH makes no difference to your results. This parameter must be enabled in order to collect channel accounting records.
To determine the value of this attribute, use the MQIA_STATISTICS_AUTO_CLUSSDR selector with the MQINQ call.