DPDK performance test results are reported for all physical testbed types present in FD.io labs and installed NIC models. For description of physical testbeds used for DPDK performance tests please refer to Physical Testbeds.
CSIT DPDK performance tests are executed on physical testbeds described in Physical Testbeds. Based on the packet path through server SUTs, one distinct logical topology type is used for DPDK DUT data plane testing: NIC-to-NIC switching topology.
The simplest logical topology for software data plane application like DPDK is NIC-to-NIC switching. Tested topologies for 2-Node and 3-Node testbeds are shown in figures below.
Server Systems Under Test (SUT) run DPDK Testpmd or L3fwd application in Linux user-mode as a Device Under Test (DUT). Server Traffic Generator (TG) runs T-Rex application. Physical connectivity between SUTs and TG is provided using different drivers and NIC models that need to be tested for performance (packet/bandwidth throughput and latency).
From SUT and DUT perspectives, all performance tests involve forwarding packets between two physical Ethernet ports (10GE, 25GE, 40GE, 100GE). In most cases both physical ports on SUT are located on the same NIC. The only exceptions are link bonding and 100GE tests. In the latter case only one port per NIC can be driven at linerate due to PCIe Gen3 x16 slot bandwidth limiations. 100GE NICs are not supported in PCIe Gen3 x8 slots.
Note that reported DPDK DUT performance results are specific to the SUTs tested. SUTs with other processors than the ones used in FD.io lab are likely to yield different results. A good rule of thumb, that can be applied to estimate DPDK packet thoughput for NIC-to-NIC switching topology, is to expect the forwarding performance to be proportional to processor core frequency for the same processor architecture, assuming processor is the only limiting factor and all other SUT parameters are equivalent to FD.io CSIT environment.
Performance Tests Coverage¶
Performance tests measure following metrics for tested DPDK DUT topologies and configurations:
Packet Throughput: measured in accordance with RFC 2544, using FD.io CSIT Multiple Loss Ratio search (MLRsearch), an optimized binary search algorithm, producing throughput at different Packet Loss Ratio (PLR) values:
Non Drop Rate (NDR): packet throughput at PLR=0%.
Partial Drop Rate (PDR): packet throughput at PLR=0.5%.
One-Way Packet Latency: measured at different offered packet loads:
100% of discovered NDR throughput.
100% of discovered PDR throughput.
Maximum Receive Rate (MRR): measured packet forwarding rate under the maximum load offered by traffic generator over a set trial duration, regardless of packet loss. Maximum load for specified Ethernet frame size is set to the bi-directional link rate.
CSIT-2009 includes following DPDK Testpmd and L3fwd data plane functionality performance tested across a range of NIC drivers and NIC models:
L2 Interface Loop forwarding all Ethernet frames between two Interfaces.
IPv4 Routed Forwarding
Longest Prefix Match (LPM) L3 IPv4 forwarding of Ethernet frames between two Interfaces, with two /8 prefixes in lookup table.