4 For description of physical testbeds used for DPDK performance tests
5 please refer to :ref:`tested_physical_topologies`.
7 .. _tested_logical_topologies:
12 CSIT DPDK performance tests are executed on physical testbeds described
13 in :ref:`tested_physical_topologies`. Based on the packet path through
14 server SUTs, one distinct logical topology type is used for DPDK DUT
17 #. NIC-to-NIC switching topologies.
22 The simplest logical topology for software data plane application like
23 DPDK is NIC-to-NIC switching. Tested topologies for 2-Node and 3-Node
24 testbeds are shown in figures below.
32 \includesvg[width=0.90\textwidth]{../_tmp/src/vpp_performance_tests/logical-2n-nic2nic}
33 \label{fig:logical-2n-nic2nic}
38 .. figure:: ../vpp_performance_tests/logical-2n-nic2nic.svg
39 :alt: logical-2n-nic2nic
49 \includesvg[width=0.90\textwidth]{../_tmp/src/vpp_performance_tests/logical-3n-nic2nic}
50 \label{fig:logical-3n-nic2nic}
55 .. figure:: ../vpp_performance_tests/logical-3n-nic2nic.svg
56 :alt: logical-3n-nic2nic
59 Server Systems Under Test (SUT) runs DPDK Testpmd/L3FWD application in
60 Linux user-mode as a Device Under Test (DUT). Server Traffic Generator (TG)
61 runs T-Rex application. Physical connectivity between SUTs and TG is provided
62 using different drivers and NIC models that need to be tested for performance
63 (packet/bandwidth throughput and latency).
65 From SUT and DUT perspectives, all performance tests involve forwarding
66 packets between two physical Ethernet ports (10GE, 25GE, 40GE, 100GE).
67 In most cases both physical ports on SUT are located on the same
68 NIC. The only exceptions are link bonding and 100GE tests. In the latter
69 case only one port per NIC can be driven at linerate due to PCIe Gen3
70 x16 slot bandwidth limiations. 100GE NICs are not supported in PCIe Gen3
73 Note that reported DPDK DUT performance results are specific to the SUTs
74 tested. SUTs with other processors than the ones used in FD.io lab are
75 likely to yield different results. A good rule of thumb, that can be
76 applied to estimate DPDK packet thoughput for NIC-to-NIC switching
77 topology, is to expect the forwarding performance to be proportional to
78 processor core frequency for the same processor architecture, assuming
79 processor is the only limiting factor and all other SUT parameters are
80 equivalent to FD.io CSIT environment.
82 Performance Tests Coverage
83 --------------------------
85 Performance tests measure following metrics for tested DPDK DUT
86 topologies and configurations:
88 - Packet Throughput: measured in accordance with :rfc:`2544`, using
89 FD.io CSIT Multiple Loss Ratio search (MLRsearch), an optimized binary
90 search algorithm, producing throughput at different Packet Loss Ratio
93 - Non Drop Rate (NDR): packet throughput at PLR=0%.
94 - Partial Drop Rate (PDR): packet throughput at PLR=0.5%.
96 - One-Way Packet Latency: measured at different offered packet loads:
98 - 100% of discovered NDR throughput.
99 - 100% of discovered PDR throughput.
101 - Maximum Receive Rate (MRR): measure packet forwarding rate under the
102 maximum load offered by traffic generator over a set trial duration,
103 regardless of packet loss. Maximum load for specified Ethernet frame
104 size is set to the bi-directional link rate.
106 |csit-release| includes following performance test suites, listed per NIC type:
108 - **L2IntLoop** - L2 Interface Loop forwarding any Ethernet frames between
111 - **IPv4 Routed Forwarding** - L3 IP forwarding of Ethernet frames between
114 Execution of performance tests takes time, especially the throughput
115 tests. Due to limited HW testbed resources available within FD.io labs
116 hosted by :abbr:`LF (Linux Foundation)`, the number of tests for some
117 NIC models has been limited to few baseline tests.
119 Performance Tests Naming
120 ------------------------
122 FD.io |csit-release| follows a common structured naming convention for
123 all performance and system functional tests, introduced in CSIT-17.01.
125 The naming should be intuitive for majority of the tests. Complete
126 description of FD.io CSIT test naming convention is provided on
127 :ref:`csit_test_naming`.