When enabled, the Multiple Context feature facilitates automatic mapping of available NUMA aligned logical cores to Rx and Tx queues of vNICs on worker nodes. This helps load balance traffic across enabled queues and can improve the total packet throughput the worker node can handle.
Multiple contexts can be configured on each vNIC of a worker node by using the ctxPerDev=[1|2|3] property on the Network Function Designer under each Network Adapter configuration in Telco Cloud Automation.
Add additionalProperties section under network > devices
Set the ctxPerDev property with the appropriate context [1|2|3]
Context 1: The Multiple Context Feature is enabled per each vNIC.
Context 2: The Multiple Context Feature is enabled for all vNICs on the VM.
Context 3: The Multiple Context Feature is enabled for each queue on each vNIC.
Using multiple (vmkernel thread) context ctxPerDev = 3 can enhance network performance on per vNIC by allowing a better load balanced distribution across the rx and tx queues. However, when enabling this value, ensure that enough CPU threads are available on an ESXi host. If more lcores are provided to a worker node, it can impact the performance of other applications. Ensure that you have an optimized design that balances throughput available not only to a specific worker node but to the overall solution.
For more details, see Configuration to Support Enhanced Data Path Support in the Telco Cloud Automation documentation.
