CPU Usage Test

Among the four components of the Cisco SD-WAN, the vEdge router can either be a Cisco SD-WAN hardware device or software that runs as a virtual machine, and the remaining three are software-only components. Generally, the software vEdge router, Cisco vManage, and Cisco vSmart Controller software run on servers, and the vBond orchestrator software runs as a process (daemon) on a vEdge router. These software-only components run on a VM with multiple vCPUs.

CPU contentions on the components can significantly degrade the performance of that component. To avoid this, administrators must track the CPU usage of each component over time, proactively detect potential CPU contentions, and accurately isolate what is causing excessive CPU usage on each component - system processes? or user processes? or being idle? This can be achieved using the CPU Usage test.

This test monitors the CPU usage of the each component of the target Cisco SD-WAN appliance and alerts administrators to erratic usage patterns on the component and what is causing them. This way, the test helps administrators isolate and pre-empt CPU contentions on the component, and thus improve the performance of the appliance.

Target of the test : Cisco SD-WAN

Agent deploying the test : An external agent

Outputs of the test : One set of the results for each component of the target Cisco SD-WAN being monitored

Configurable parameters for the test

Parameter	Description
Test period	How often should the test be executed
Host	The IP address of the host for which this test is to be configured.
Port	Specify the port at which the specified Host listens to. By default, this is NULL.
Username	By default, the eG agent executes REST APIs on the target appliance to collect the required metrics. For the eG agent to execute the REST APIs, a special user with monitoring privilege is required. Specify the name of such a user in this text box.
Password	Specify the password corresponding to the user mentioned in the Username text box here.
Confirm Password	Confirm the Password by retyping it here.
REST API Port	By default, the REST API Port is set to none. This implies that by default, this test connects to the default port to execute the REST API commands and collect the required metrics. In some environments however, a different port can be used to execute the REST API commands. In such case, specify that port number against the REST API Port text box.
SSL	The eG agent collects performance metrics by executing REST APIs on the target appliance. Typically, the REST APIs can be invoked through HTTP or HTTPS mode. By default, the eG agent invokes REST APIs using the HTTPS mode. This is why, the SSL flag is set to Yes by default. If the target appliance is not SSL-enabled, then the REST APIs can be accessed through HTTP mode only. In this case, set the SSL flag to No.

Measurements made by the test

Measurement	Description	Measurement Unit	Interpretation
User CPU	Indicates the percentage of CPU consumed by the user process of this component.	Percent	By comparing the value of this measure with that of the System CPU and Idle CPU measures, you can instantly determine whether system processes are CPU-hungry or user processes or the idle time the cause of CPU contention.
System CPU	Indicates the percentage of CPU consumed by the system process of this component.	Percent	By comparing the value of this measure with that of the User CPU and Idle CPU measures, you can instantly determine whether system processes are CPU-hungry or user processes or the idle time the cause of CPU contention.
Idle CPU	Indicates the percentage of CPU that is idle for this component.	Percent	Compare the value of this measure with the value of the System CPU and User CPU, measures to understand where the component spent the maximum CPU time - in serving user requests? in system-level processing? or being idle? In the event of a slowdown, you can use the results of this comparative analysis to determine what caused the CPU contention.