Configuring the IMS Message Queue

You can configure the IMS message queue to best serve the application or applications that run in an enterprise server region. You can modify default settings before starting the region. Once started, some of these settings are static, meaning that changes cannot be applied until the region is restarted. Others are dynamic, meaning that you can change and apply the settings without restarting the region.

Most IMS message queue options can be set from the Enterprise Server Administration Server > Properties > MSS > IMS > TM > General page. See Server Instance Properties: MSS IMS TM General for a detailed description of each option including default values.

Static Options

Before starting your enterprise server region, you can replace the default for any static IMS message queue option with an alternative initial setting. Static IMS message queue configuration options include:

  • (Message queue) Name
  • Queue buffer count
  • MFS path
  • MFS attribute bias
  • MFS null character
  • Application path

After starting the region, any changes made to these settings cannot be applied until the region is restarted.

Dynamic Options

Just as with the static options, you can use the default or provide a custom initial value for most dynamic IMS message queue options. However, you can also change the value of a dynamic option while the enterprise server region is running, with the new value taking effect immediately. You can:

  • Adjust the data store size limit
  • Adjust the data store allocation cushion size
  • Adjust the length of time that a transaction can run
  • Adjust the generation frequency of keypoints
  • Tune the flush aggregation performance behavior

You can assign an initial value for the following dynamic settings from the Enterprise Server Administration Server > Properties > MSS > IMS > TM > General page:

  • Maximum Blocks
  • Activity keypoint frequency
  • Transaction threshold

The initial configuration for other dynamic IMS message queue options are based on the values set by ES_TMC_AGGREGATE environment variable.

Once the enterprise server region is started, you can make changes to dynamic IMS message queue options from ESMAC on the IMS Control page.

The following topics provide additional details for dynamic IMS message queue configuration: