Cisco Cisco Packet Data Gateway (PDG)
SaMOG Gateway Overview
Features and Functionality - Base Software ▀
SaMOG Administration Guide, StarOS Release 17 ▄
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used. Regardless, the directory can be on a local file system or on an NFS-mounted file system on the Web Element
Manager server.
Manager server.
Important:
For more information on bulk statistics, see the System Administration Guide.
Congestion Control Support
SaMOG enhances on the StarOS framework to provide congestion control policies and threshold crossing alerts to
ensure smooth performance of the SaMOG service and prevent congestion. The Congestion Control feature enables
policies and thresholds to be configured to specify how the system should react in the event of a heavy load condition.
ensure smooth performance of the SaMOG service and prevent congestion. The Congestion Control feature enables
policies and thresholds to be configured to specify how the system should react in the event of a heavy load condition.
Congestion control monitors the system for conditions that could potentially degrade performance when the system is
under heavy load. Typically, these conditions are temporary (for example, high CPU or memory utilization) and are
quickly resolved. However, continuous or large numbers of these conditions within a specific time interval may have an
impact the system’s ability to service subscriber sessions. Congestion control helps identify such conditions and invokes
policies for addressing the situation.
under heavy load. Typically, these conditions are temporary (for example, high CPU or memory utilization) and are
quickly resolved. However, continuous or large numbers of these conditions within a specific time interval may have an
impact the system’s ability to service subscriber sessions. Congestion control helps identify such conditions and invokes
policies for addressing the situation.
Congestion control operation is based on configuring the following:
Congestion Condition Thresholds: Thresholds dictate the conditions for which congestion control is enabled
and establish limits for defining the state of the system (congested or clear). These thresholds function in a way
similar to operational thresholds that are configured for the system as described in the Thresholding
Configuration Guide. The primary difference is that when congestion thresholds are reached, a service
congestion policy and an SNMP trap, starCongestion, are generated.
similar to operational thresholds that are configured for the system as described in the Thresholding
Configuration Guide. The primary difference is that when congestion thresholds are reached, a service
congestion policy and an SNMP trap, starCongestion, are generated.
A threshold tolerance dictates the percentage under the configured threshold that must be reached in order for
the condition to be cleared. An SNMP trap, starCongestionClear, is then triggered.
the condition to be cleared. An SNMP trap, starCongestionClear, is then triggered.
Port Utilization Thresholds: If you set a port utilization threshold, when the average utilization of all
ports in the system reaches the specified threshold, congestion control is enabled.
Port-specific Thresholds: If you set port-specific thresholds, when any individual port-specific
threshold is reached, congestion control is enabled system-wide.
Service Congestion Policies: Congestion policies are configurable for each service. These policies dictate how
services respond when the system detects that a congestion condition threshold has been crossed.
For the SaMOG Gateway, congestion control monitors the following resources:
Licensing utilization
Maximum sessions per service utilization
Demux message queue utilization
Demux message queue wait time
Port Rx specific utilization
Port Tx specific utilization
Averate transmit port Tx utilization
Process CPU utilization
System CPU utilization
System memory utilization