CPU Overload Protection

Communications Server enables you to regulate incoming HTTP and SIP requests based on the CPU load. CPU overload protection can be activated or de-activated both during installation and in runtime.

To enable CPU overload protection, set the CPUOverLoadRegulation property to true. By default, this value this set to false. Use the following command to set this property:

asadmin set config.sip-container.property.CPUOverLoadRegulation=true

You can configure the following threshold levels:

• HttpThreshold - All incoming HTTP requests are rejected and 503 responses are sent out, when this threshold is exceeded.

• IrThreshold - Initial incoming requests are rejected and 503 responses are sent out when this threshold is exceeded.

• SrThreshold - All incoming SIP requests are rejected and 503 responses are sent out, when this threshold is exceeded.

• MmThreshold - All incoming HTTP and SIP requests are rejected when this threshold is exceeded.

• SampleRate - Interval or periodicity of the measurement of CPU usage.

• NumberOfSamples -Number of samples that the CPU usage has to be above the threshold level to trigger an action of either dropping the request or sending 503 responses.

For details about these properties, such as default value and allowed values see TBDlink.

These CPU load regulation properties are applicable only if the CPUOverLoadRegulation property needs to be set to true. To view and set these values, use the asadmin get and set commands. For example, you can use the following command to set the value of the IrThreshold property:

asadmin set config.sip-container.property.IrThreshold=80