The following presentation describe how routing and switching on software does minimal impact on hardware. During the test we a physical layer (servers and switches) where we ran some load test but with VMware NSX all the network function such switching L2, Routing L3 and Firewall L4 can be done in Software with no overhead.
We have enable and tunned all NIC cards to offset module like TCP checksum offload KB 2052904, large receive offload and TCP segmentation offload KB 2055140 and receive side scaling (RSS) KB 2008925 as per hardware vendor and VMware manual enable offset to supported hardware increase performance up to 50%.
We generate traffic using NETPERF on 4 VMs per cluster. When we were working on traditional VLANs, we got 18Gbps throughput but on VMware NSX, we got identical result only a slight CPU was observed but not 100% related to the routing in Software capability.
The Final test was to test distributed FW capability, so we placed virtual Machines and create 100 firewall rules ( allow-deny-block) without any impact on Bandwidth and latency once we passed all test with 100 rules we created a set of 500 firewall rules where metrics remain identical meaning that number of rules didn’t impact performance.
NOTE: All these test were running on the Dell Solution Centre using new hardware.