Settings for the Notification Message Queue - SAP Documentation

Settings for the Notification Message Queue

Procedure

On the Host tab in the Notification Message Queue and Dispatch Settings screen area, you can make the following settings:

Field	Description
Process Notification Messages Exactly Once in Order	If you select this checkbox, the notification messages are delivered individually and in the order in which they were placed in the queue in accordance with the delivery type Exactly Once in Order. Note In this case, the delivery of the messages is sequential. The Max. Dispatch Threads field is not relevant to the delivery type Exactly Once in Order and so you cannot change it. End of the note. If a notification message cannot be delivered, this notification message then blocks the sending of any further messages to prevent one of these other messages being delivered first. The notification message that cannot be delivered is displayed on the Message Retries tab. A notification message that cannot be delivered remains in the main queue until it can be delivered successfully. If the maximum number of retries is reached and the notification message could still not be delivered, PCo stops the sending of the notification message. The failed notification message remains in the main queue so that it can be sent again as soon as you restart the agent. (See also: Microsoft Message Queuing (MSMQ).) If you do not select the checkbox, the notification messages are sent in parallel processes. For this, you can specify the maximum number of dispatch threads. PCo tries to automatically resend messages that could not be delivered successfully. (See: Notification: Reliable Connection Tab and Agent Instance: Displaying Messages.)
Keep Copies of Queued Notification Messages in Journal Queue	If you select this checkbox, a copy of each notification message is stored in the Journal Messages folder of the Microsoft Message Queuing component. (see also: Microsoft Message Queuing (MSMQ) Note The Journal Message Queue folder is located, for example, in Windows 7 under Control Panel Administrative Tools Computer Management Services and Applications Message Queuing System Queues Journal Messages . End of the note. You should only use this setting in the test phase for testing and for tracking errors, otherwise the contents of the directory can become too large and can have an adverse effect on performance.
Make Queued Notification Messages Recoverable	If you select the checkbox, MSMQ stores the notification messages on the hard disk. The notification messages then remain in the queue even if Windows has to be restarted. If you do not select the checkbox, the notification messages are only saved in the working memory. This leads to a better performance. Irrespective of this checkbox, notification messages are kept in the queue if the agent instance has to be restarted.
Maximum number of queued messages	This field specifies the maximum number of notification messages that are allowed to be in the message queue. This includes messages on the Queued Messages and Message Failures tabs. When the specified number of messages has accumulated, the connection to the source system is terminated and the agent instance gets the status Error. You can enter values `between 10 and 10000`. The default value is 1000. At 80% of the value, the system issues a warning of the event type Critical in the message log. If you start the agent instance again when the maximum number of messages has already been exceeded, the upper limit is increased temporarily to 120% of the value so that you can resolve the situation when the agent instance is running.
Max. Dispatch Threads	This field specifies the maximum number of threads per processor that are to be used for the asynchronous, parallel sending of notifications. The limits of this field are a minimum of 10 threads per processor and a maximum of 250 threads per processor. You can specify a maximum number of dispatch threads here. Note Ensure that the correct number of threads is also provided at the recipient. The Max. Dispatch Threads field is not relevant to the delivery type Exactly Once in Order and so you cannot change it. In the case of the delivery type Exactly Once in Order, delivery is always synchronous and sequential. : End of the note.

More Information

Microsoft Message Queuing (MSMQ)