2.2.1 Impact of Adding Rule Templates

Using the mediation framework to manipulate messages can result in increased CPU usage. The CPU increase is dependent on the several factors including the type and number of searches as well as the number and types of changes being performed to the messages. For example, a simple numeric search or an action such as deleting an AVP may not result in increased CPU usage, but a search and replace based on complex pattern matching likely results in increased CPU usage.

The Mediation framework supports a large number of conditions, operators and actions and it is not practical to quantify the CPU increase for every possible combination of conditions and actions. For network planners and operations teams planning to use Mediation, this document provides guidance on the impact of given Mediation template and its associated rules.

While the system allows a maximum of 64 active templates, operators should be cautious about activating templates as it may impact performance. Assessing a Rule Template for Safe Use provides steps an operator can use to ensure that DSR can continue to support the capacity it has been deployed for, along with the planned mediation templates/rules.

Note:

Operators on DSR releases 7.1.x to 7.x.x releases are required to run an additional MOP to unlock the number of templates that can be activated. Raising the Limit of Active Rule Templates provides steps to increase the number of templates.

Note:

There is no performance impact to the DSR for having templates in the Development or Test state or for having an template in the Active state but not assigned to a trigger point.

The Diameter Routing Layer (DRL) request task (DRLRequestTask) and the DRL answer task ( DRLAnswerTask) are processes that run on the DSR and are the work horses in the routing layer. These tasks are also responsible for all mediation related activities. Specifically, the DRLRequestTask, among other things, is responsible for any mediation performed on Request messages and therefore the performance impact of using a template at one of the Request Trigger Points is reflected in the %CPU usage of the DrlRequestTask processes.

Similarly, the DRLAnswerTask is responsible for any mediation performed on the Answer messages and the corresponding performance impact is reflected in %CPU usage or the DrlAnswerTask processes. It should be noted that on any given system, there are multiple instances of the DRLRequestTask and DRLAnswerTask processes.

Assessing a Rule Template for Safe Use the steps to monitor these processes and the permissible limits under which they should remain to ensure that the DSR can support the traffic it was engineered for.