Cyclic Test

Updated by Bryan Jones

Cyclic Test

Cyclic Test is intended to determine a platform's viability without adding any additional load beyond what the reader needs the base system to support. NO Telos Alliance audio products should be loaded. Telos Alliance does recommend having utilities like TelosConnect, TeamViewer, NGINX, and the Telos Alliance License Server if needed. These are base level services and testing should account for them. Follow the steps below to conduct the base cyclic test.

Run the command sudo apt install rt-tests

Run the command sudo cyclictest --mlockall --smp --priority=80 --interval=1000 --distance=0

Leave the system running for 24 hours with the terminal connected.

The terminal should fill with outputs from the cyclic test. Review these output messages and verify the MAX value does not exceed 150 µ seconds.

Results will look similar to this. One line per CPU core with the MAX: number all the way to the right.

If the test results prove the platform can achieve 150 µ seconds or less the platform will likely support AoIP. In the event the platform cannot achieve 150 µ seconds or less, the system cannot support Audio Over IP products from Telos. This may be a hardware limitation, or it could be due to existing load on the system. The reader may attempt to remove other services from the server, but there is no guarantee this will allow the platform to achieve latency sufficient for AoIP Products to operate.

If a system passes all cyclic tests, the CPU has a high probability of supporting AoIP products. Please note that this document does not take networking into consideration. Network latency and bandwidth are two major system bottlenecks. Both latency and bandwidth are affected by the CPU and network interface. Generally speaking it is not recommend to exceed 50% utilization of a given link. This constrains the physical network interface.By default the operating system may not reserve any resource from the CPU for networking. When this is the case it is possible a system will produce audible defects, even with 150 µ seconds or lower of system latency. If this is the case system must be reconfigured to provide discrete CPU resources for network traffic. Please note that this changes depending on the Operating System.

If a system passes all of the tests listed in this document, there is sufficient bandwidth, and the network latency is low enough then the platform should support AoIP products.

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