DA-MP Overload Control (Message Priority and Color-Based DA-MP Overload Control) provides a mechanism for managing internal/local DA-MP congestion detection and control.
The DA-MP Overload Control feature tracks ingress message rate, calculates the amount of traffic that needs to be shed based on CPU congestion, and sheds that traffic based on Message Priority, Message Color, and discard policy.
Message Color is used as a means for differentiating Diameter Connections that are under-utilized versus those that are over-utilized with respect to ingress traffic - traffic from under-utilized Connections is marked "green" by the Per-Connection Ingress MPS Control (PCIMC) feature, while traffic from over-utilized Connections is marked "yellow". In the event of (Danger of Congestion or of CPU congestion and based on the specified discard policy, traffic from over-utilized Connections is considered for discard before traffic from under-utilized Connections. Traffic discarded by PCIMC due to capacity exhaustion (per-Connection or shared) is marked "red" and is not considered for any subsequent processing.
The availability of key traffic-sensitive internal software resources (stack queues and buffer pools) is monitored in real-time against their static maximum capacity.
When resource availability drops below engineered thresholds, alarms are generated. When resource availability is exhausted, controls are invoked to prevent over-utilization. Resource utilization KPIs and measurements provide real-time and long-term information for making decisions about system capacity and growth.
Traffic loads, if allowed to exceed the DA-MP's engineered capacity, will degrade the effective performance of the DA-MP, increase message latency, and can result in message loss. DA-MP Overload Control is responsible for reducing the traffic processing load to insure that the MP meets its performance specifications. MP Processing Overload Control monitors the Diameter Process CPU utilization of the Diameter Process.
A DA-MP Profile is assigned to each DA-MP in the system. See the MP Profiles information in Diameter Common User's Guide.
The assigned DA-MP Profile indicates the Engineered Maximum MPS for the DA-MP and the Message Rate Alarm Set and Clear Thresholds. These engineering-configured MP Profiles values shown on the MPs menu vary depending on the type of blade or Rack Mount Server used for the DA-MP.
A Routing Option Set is a set of user-configurable routing options assigned to an ingress Diameter transaction. A Routing Option Set can be assigned to Peer Nodes and Diameter Application IDs.