Enabling Performance Mode or Lite Mode

vMX can be configured to run in two modes depending on the use case.

• Lite mode—Needs fewer resources in terms of CPU and memory to run at lower bandwidth.

• Performance mode—Needs higher resources in terms of CPU and memory to run at higher bandwidth.

  Note:

  Performance mode is enabled implicitly by default.

  When you enable performance mode, make sure you have configured the proper number of vCPUs and memory for your VMs based on your use case.

  To calculate the minimum number of vCPUs needed by VFP for performance mode: (4 * number-of-ports) + 4.

You can explicitly enable performance mode by including the performance-mode statement at the [edit chassis fpc 0] hierarchy level.

If you are using paravirtualized network interfaces such as virtio (for KVM) or VMXNET3 (for VMware) for lab simulation use cases, you can disable performance mode by including the lite-mode statement at the [edit chassis fpc 0] hierarchy level.

Table 1 highlights some of the challenging features which are supported in the Fast Path and some which are not supported. Features which are not supported in the Fast Path still work but they get less than 100K PPS per worker vCPU.