Attributes that control real-time monitoring

Some queue and channel status attributes hold monitoring information, if real-time monitoring is enabled. If real-time monitoring is not enabled, no monitoring information is held in these monitoring attributes. Examples demonstrate how we can use these queue and channel status attributes.

We can enable or disable real-time monitoring for individual queues or channels, or for multiple queues or channels. To control individual queues or channels, set the queue attribute MONQ or the channel attribute MONCHL, to enable or disable real-time monitoring. To control many queues or channels together, enable or disable real-time monitoring at the queue manager level by using the queue manager attributes MONQ and MONCHL. For all queue and channel objects with a monitoring attribute that is specified with the default value, QMGR, real-time monitoring is controlled at the queue manager level.

Automatically defined cluster-sender channels are not IBM MQ objects, so do not have attributes in the same way as channel objects. To control automatically defined cluster-sender channels, use the queue manager attribute, MONACLS. This attribute determines whether automatically defined cluster-sender channels within a queue manager are enabled or disabled for channel monitoring.

For real-time monitoring of channels, we can set the MONCHL attribute to one of the three monitoring levels: low, medium, or high. We can set the monitoring level either at the object level or at the queue manager level. The choice of level is dependent on the system. Collecting monitoring data might require some instructions that are relatively expensive computationally, such as obtaining system time. To reduce the effect of real-time monitoring, the medium and low monitoring options measure a sample of the data at regular intervals rather than collecting data all the time. Table 1 summarizes the monitoring levels available for real-time monitoring of channels:

Level	Description	Usage
Low	Measure a small sample of the data, at regular intervals.	For objects that process a high volume of messages.
Medium	Measure a sample of the data, at regular intervals.	For most objects.
High	Measure all data, at regular intervals.	For objects that process only a few messages per second, on which the most current information is important.

For real-time monitoring of queues, we can set the MONQ attribute to one of the three monitoring levels, low, medium or high. However, there is no distinction between these values. The values all enable data collection, but do not affect the size of the sample.

Examples

The following examples demonstrate how to set the necessary queue, channel, and queue manager attributes to control the level of monitoring. For all of the examples, when monitoring is enabled, queue and channel objects have a medium level of monitoring.

1. To enable both queue and channel monitoring for all queues and channels at the queue manager level, use the following commands:

   ALTER QMGR MONQ(MEDIUM) MONCHL(MEDIUM)
   ALTER QL(Q1) MONQ(QMGR)
   ALTER CHL(QM1.TO.QM2) CHLTYPE(SDR) MONCHL(QMGR)
   

2. To enable monitoring for all queues and channels, with the exception of local queue, Q1, and sender channel, QM1.TO.QM2, use the following commands:

   ALTER QMGR MONQ(MEDIUM) MONCHL(MEDIUM)
   ALTER QL(Q1) MONQ(OFF)
   ALTER CHL(QM1.TO.QM2) CHLTYPE(SDR) MONCHL(OFF)
   

3. To disable both queue and channel monitoring for all queues and channels, with the exception of local queue, Q1, and sender channel, QM1.TO.QM2, use the following commands:

   ALTER QMGR MONQ(OFF) MONCHL(OFF)
   ALTER QL(Q1) MONQ(MEDIUM)
   ALTER CHL(QM1.TO.QM2) CHLTYPE(SDR) MONCHL(MEDIUM)
   

4. To disable both queue and channel monitoring for all queues and channels, regardless of individual object attributes, use the following command:

   ALTER QMGR MONQ(NONE) MONCHL(NONE)
   

5. To control the monitoring capabilities of automatically defined cluster-sender channels use the following command:

   ALTER QMGR MONACLS(MEDIUM)
   

6. To specify that automatically defined cluster-sender channels are to use the queue manager setting for channel monitoring, use the following command:

   ALTER QMGR MONACLS(QMGR)
   

Parent topic: Real-time monitoring

Related concepts

• Real-time monitoring
• Use IBM MQ online monitoring

Related tasks

• Display queue and channel monitoring data

Related information

• Display and alter queue manager attributes
• Monitor (MONCHL)