Enable Receive Side Scaling (RSS) on ESXi

Products

• VMware vSphere ESXi

Issue/Introduction

Receive Side Scaling (RSS) is a feature that allows network packets from a single NIC to be scheduled in parallel on multiple CPUs by creating multiple hardware queues.
While this might increase network throughput for a NIC that receives packets at a high rate, it can also increase CPU overhead.

When using certain 10Gb/s or faster Ethernet physical NICs, ESXi allows the RSS capabilities of the physical NICs to be used by the virtual NICs.
This can be especially useful in environments where a single MAC address gets large amounts of network traffic (for example VXLAN or network-intensive virtual appliances).
Because of the potential for increased CPU overhead, this feature is deactivated by default.

Environment

VMware vSphere ESXi 7.x 
VMware vSphere ESXi 8.x

Resolution

To enable RSS on NIC drivers

esxcli system module parameters set -a -m driver_name -p RSS="1"

To activate the feature on multiple NICs (  three NIC )

esxcli system module parameters set -a -m driver_name -p RSS="1,1,1"

Additional Information

Referred to Page 50 for details on configuring RSS : Vsphere esxi and vcenter Server performance best practices