Enable Software Receive Side Scaling

You can improve VLAN-VXLAN bridging throughput using Software Receive Side Scaling.

Prerequisites

• Verify that you have NSX 6.4.2 or later installed.
• Determine which hosts should have SoftRSS enabled.
  • Enable SoftRSS on the ESXi hosts on which the active/standby bridge exists (where the DLR Control VMs are hosted). If the Control VMs might be migrated using vMotion, enable SoftRSS on all the hosts in the cluster.
  • If Default Queue Receive Side Scaling (DRSS) is supported on the host physical NIC, enable that and do not enable SoftRSS. Use esxcli system module parameters list -m [nic_module] to verify if DRSS is supported.

Procedure

1. Enable SoftRSS on a host.
   The recommended value for number of worlds for a 10G uplink is 4.

   You can increase the number of worlds up to a maximum of 16. You might want to increase the number if the uplink can support a higher rate (using link aggregation) or if you notice an uneven distribution of flows to the worlds based on your traffic pattern.

   net-dvs -s com.vmware.net.vdr.softrss=[number of worlds] -p hostPropList [dvs name]

2. (Optional) If you want to disable SoftRSS, use this command.

   net-dvs -u com.vmware.net.vdr.softrss -p hostPropList [dvs name]