Internet Engineering Task Force (IETF)                         M. Tahhan
Request for Comments: 8204                                   B. O'Mahony
Category: Informational                                            Intel
ISSN: 2070-1721                                                A. Morton
                                                              AT&T Labs
                                                         September 2017


  Benchmarking Virtual Switches in the Open Platform for NFV (OPNFV)

Abstract

  This memo describes the contributions of the Open Platform for NFV
  (OPNFV) project on Virtual Switch Performance (VSPERF), particularly
  in the areas of test setups and configuration parameters for the
  system under test.  This project has extended the current and
  completed work of the Benchmarking Methodology Working Group in the
  IETF and references existing literature.  The Benchmarking
  Methodology Working Group has traditionally conducted laboratory
  characterization of dedicated physical implementations of
  internetworking functions.  Therefore, this memo describes the
  additional considerations when virtual switches are implemented on
  general-purpose hardware.  The expanded tests and benchmarks are also
  influenced by the OPNFV mission to support virtualization of the
  "telco" infrastructure.

Status of This Memo

  This document is not an Internet Standards Track specification; it is
  published for informational purposes.

  This document is a product of the Internet Engineering Task Force
  (IETF).  It represents the consensus of the IETF community.  It has
  received public review and has been approved for publication by the
  Internet Engineering Steering Group (IESG).  Not all documents
  approved by the IESG are a candidate for any level of Internet
  Standard; see Section 2 of RFC 7841.

  Information about the current status of this document, any errata,
  and how to provide feedback on it may be obtained at
  https://www.rfc-editor.org/info/rfc8204.










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Copyright Notice

  Copyright (c) 2017 IETF Trust and the persons identified as the
  document authors.  All rights reserved.

  This document is subject to BCP 78 and the IETF Trust's Legal
  Provisions Relating to IETF Documents
  (https://trustee.ietf.org/license-info) in effect on the date of
  publication of this document.  Please review these documents
  carefully, as they describe your rights and restrictions with respect
  to this document.  Code Components extracted from this document must
  include Simplified BSD License text as described in Section 4.e of
  the Trust Legal Provisions and are provided without warranty as
  described in the Simplified BSD License.

Table of Contents

  1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   3
    1.1.  Requirements Language . . . . . . . . . . . . . . . . . .   4
    1.2.  Abbreviations . . . . . . . . . . . . . . . . . . . . . .   4
  2.  Scope . . . . . . . . . . . . . . . . . . . . . . . . . . . .   5
  3.  Benchmarking Considerations . . . . . . . . . . . . . . . . .   5
    3.1.  Comparison with Physical Network Functions  . . . . . . .   5
    3.2.  Continued Emphasis on Black-Box Benchmarks  . . . . . . .   6
    3.3.  New Configuration Parameters  . . . . . . . . . . . . . .   6
    3.4.  Flow Classification . . . . . . . . . . . . . . . . . . .   8
    3.5.  Benchmarks Using Baselines with Resource Isolation  . . .   9
  4.  VSPERF Specification Summary  . . . . . . . . . . . . . . . .  11
  5.  3x3 Matrix Coverage . . . . . . . . . . . . . . . . . . . . .  18
    5.1.  Speed of Activation . . . . . . . . . . . . . . . . . . .  19
    5.2.  Accuracy of Activation  . . . . . . . . . . . . . . . . .  19
    5.3.  Reliability of Activation . . . . . . . . . . . . . . . .  19
    5.4.  Scale of Activation . . . . . . . . . . . . . . . . . . .  19
    5.5.  Speed of Operation  . . . . . . . . . . . . . . . . . . .  19
    5.6.  Accuracy of Operation . . . . . . . . . . . . . . . . . .  19
    5.7.  Reliability of Operation  . . . . . . . . . . . . . . . .  20
    5.8.  Scalability of Operation  . . . . . . . . . . . . . . . .  20
    5.9.  Summary . . . . . . . . . . . . . . . . . . . . . . . . .  20
  6.  Security Considerations . . . . . . . . . . . . . . . . . . .  21
  7.  References  . . . . . . . . . . . . . . . . . . . . . . . . .  21
    7.1.  Normative References  . . . . . . . . . . . . . . . . . .  21
    7.2.  Informative References  . . . . . . . . . . . . . . . . .  22
  Acknowledgements  . . . . . . . . . . . . . . . . . . . . . . . .  23
  Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  24







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1.  Introduction

  The Benchmarking Methodology Working Group (BMWG) has traditionally
  conducted laboratory characterization of dedicated physical
  implementations of internetworking functions.  The black-box
  benchmarks of throughput, latency, forwarding rates, and others have
  served our industry for many years.  Now, Network Function
  Virtualization (NFV) has the goal of transforming how internetwork
  functions are implemented and therefore has garnered much attention.

  A virtual switch (vSwitch) is an important aspect of the NFV
  infrastructure; it provides connectivity between and among physical
  network functions and virtual network functions.  As a result, there
  are many vSwitch benchmarking efforts but few specifications to guide
  the many new test design choices.  This is a complex problem and an
  industry-wide work in progress.  In the future, several of BMWG's
  fundamental specifications will likely be updated as more testing
  experience helps to form consensus around new methodologies, and BMWG
  should continue to collaborate with all organizations that share the
  same goal.

  This memo describes the contributions of the Open Platform for NFV
  (OPNFV) project on Virtual Switch Performance (VSPERF)
  characterization through the Danube 3.0 (fourth) release [DanubeRel]
  to the chartered work of the BMWG (with stable references to their
  test descriptions).  This project has extended the current and
  completed work of the BMWG IETF and references existing literature.
  For example, the most often referenced RFC is [RFC2544] (which
  depends on [RFC1242]), so the foundation of the benchmarking work in
  OPNFV is common and strong.  The recommended extensions are
  specifically in the areas of test setups and configuration parameters
  for the system under test.

  See [VSPERFhome] for more background and the OPNFV website for
  general information [OPNFV].

  The authors note that OPNFV distinguishes itself from other open
  source compute and networking projects through its emphasis on
  existing "telco" services as opposed to cloud computing.  There are
  many ways in which telco requirements have different emphasis on
  performance dimensions when compared to cloud computing: support for
  and transfer of isochronous media streams is one example.









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1.1.  Requirements Language

  The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
  "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
  "OPTIONAL" in this document are to be interpreted as described in
  BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all
  capitals, as shown here.

1.2.  Abbreviations

  For the purposes of this document, the following abbreviations apply:

   ACK      Acknowledge
   ACPI     Advanced Configuration and Power Interface
   BIOS     Basic Input Output System
   BMWG     Benchmarking Methodology Working Group
   CPDP     Control Plane Data Plane
   CPU      Central Processing Unit
   DIMM     Dual In-line Memory Module
   DPDK     Data Plane Development Kit
   DUT      Device Under Test
   GRUB     Grand Unified Bootloader
   ID       Identification
   IMIX     Internet Mix
   IP       Internet Protocol
   IPPM     IP Performance Metrics
   LAN      Local Area Network
   LTD      Level Test Design
   NFV      Network Functions Virtualization
   NIC      Network Interface Card
   NUMA     Non-uniform Memory Access
   OPNFV    Open Platform for NFV
   OS       Operating System
   PCI      Peripheral Component Interconnect
   PDV      Packet Delay Variation
   SR/IOV   Single Root / Input Output Virtualization
   SUT      System Under Test
   TCP      Transmission Control Protocol
   TSO      TCP Segment Offload
   UDP      User Datagram Protocol
   VM       Virtual Machine
   VNF      Virtualised Network Function
   VSPERF   OPNFV vSwitch Performance Project








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2.  Scope

  The primary purpose and scope of the memo is to describe key aspects
  of vSwitch benchmarking, particularly in the areas of test setups and
  configuration parameters for the system under test, and extend the
  body of extensive BMWG literature and experience.  Initial feedback
  indicates that many of these extensions may be applicable beyond this
  memo's current scope (to hardware switches in the NFV infrastructure
  and to virtual routers, for example).  Additionally, this memo serves
  as a vehicle to include more detail and relevant commentary from BMWG
  and other open source communities under BMWG's chartered work to
  characterize the NFV infrastructure.

  The benchmarking covered in this memo should be applicable to many
  types of vSwitches and remain vSwitch agnostic to a great degree.
  There has been no attempt to track and test all features of any
  specific vSwitch implementation.

3.  Benchmarking Considerations

  This section highlights some specific considerations (from [RFC8172])
  related to benchmarks for virtual switches.  The OPNFV project is
  sharing its present view on these areas as they develop their
  specifications in the Level Test Design (LTD) document as defined by
  [IEEE829].

3.1.  Comparison with Physical Network Functions

  To compare the performance of virtual designs and implementations
  with their physical counterparts, identical benchmarks are needed.
  BMWG has developed specifications for many physical network
  functions.  The BMWG has recommended reusing existing benchmarks and
  methods in [RFC8172], and the OPNFV LTD expands on them as described
  here.  A key configuration aspect for vSwitches is the number of
  parallel CPU cores required to achieve comparable performance with a
  given physical device or whether some limit of scale will be reached
  before the vSwitch can achieve the comparable performance level.

  It's unlikely that the virtual switch will be the only application
  running on the SUT, so CPU utilization, cache utilization, and memory
  footprint should also be recorded for the virtual implementations of
  internetworking functions.  However, internally measured metrics such
  as these are not benchmarks; they may be useful for the audience
  (e.g., operations) to know and may also be useful if there is a
  problem encountered during testing.






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  Benchmark comparability between virtual and physical/hardware
  implementations of equivalent functions will likely place more
  detailed and exact requirements on the "testing systems" (in terms of
  stream generation, algorithms to search for maximum values, and their
  configurations).  This is another area for standards development to
  appreciate; however, this is a topic for a future document.

3.2.  Continued Emphasis on Black-Box Benchmarks

  External observations remain essential as the basis for benchmarks.
  Internal observations with a fixed specification and interpretation
  will be provided in parallel to assist the development of operations
  procedures when the technology is deployed.

3.3.  New Configuration Parameters

  A key consideration when conducting any sort of benchmark is trying
  to ensure the consistency and repeatability of test results.  When
  benchmarking the performance of a vSwitch, there are many factors
  that can affect the consistency of results; one key factor is
  matching the various hardware and software details of the SUT.  This
  section lists some of the many new parameters that this project
  believes are critical to report in order to achieve repeatability.

  It has been the goal of the project to produce repeatable results,
  and a large set of the parameters believed to be critical is provided
  so that the benchmarking community can better appreciate the increase
  in configuration complexity inherent in this work.  The parameter set
  below is assumed sufficient for the infrastructure in use by the
  VSPERF project to obtain repeatable results from test to test.

  Hardware details (platform, processor, memory, and network)
  including:

  o  BIOS version, release date, and any configurations that were
     modified

  o  Power management at all levels (ACPI sleep states, processor
     package, OS, etc.)

  o  CPU microcode level

  o  Number of enabled cores

  o  Number of cores used for the test

  o  Memory information (type and size)




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  o  Memory DIMM configurations (quad rank performance may not be the
     same as dual rank) in size, frequency, and slot locations

  o  Number of physical NICs and their details (manufacturer, versions,
     type, and the PCI slot they are plugged into)

  o  NIC interrupt configuration (and any special features in use)

  o  PCI configuration parameters (payload size, early ACK option,
     etc.)

  Software details including:

  o  OS RunLevel

  o  OS version (for host and VNF)

  o  Kernel version (for host and VNF)

  o  GRUB boot parameters (for host and VNF)

  o  Hypervisor details (type and version)

  o  Selected vSwitch, version number, or commit ID used

  o  vSwitch launch command line if it has been parameterized

  o  Memory allocation to the vSwitch

  o  Which NUMA node it is using and how many memory channels

  o  DPDK or any other software dependency version number or commit ID
     used

  o  Memory allocation to a VM - if it's from Hugepages/elsewhere

  o  VM storage type - snapshot, independent persistent, independent
     non-persistent

  o  Number of VMs

  o  Number of virtual NICs (vNICs) - versions, type, and driver

  o  Number of virtual CPUs and their core affinity on the host

  o  Number of vNICs and their interrupt configurations





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  o  Thread affinitization for the applications (including the vSwitch
     itself) on the host

  o  Details of resource isolation, such as CPUs designated for Host/
     Kernel (isolcpu) and CPUs designated for specific processes
     (taskset).

  Test traffic information:

  o  Test duration

  o  Number of flows

  o  Traffic type - UDP, TCP, and others

  o  Frame Sizes - fixed or IMIX [RFC6985] (note that with
     [IEEE802.1ac], frames may be longer than 1500 bytes and up to 2000
     bytes)

  o  Deployment Scenario - defines the communications path in the SUT

3.4.  Flow Classification

  Virtual switches group packets into flows by processing and matching
  particular packet or frame header information, or by matching packets
  based on the input ports.  Thus, a flow can be thought of as a
  sequence of packets that have the same set of header field values or
  have arrived on the same physical or logical port.  Performance
  results can vary based on the parameters the vSwitch uses to match
  for a flow.  The recommended flow classification parameters for any
  vSwitch performance tests are: the input port (physical or logical),
  the source MAC address, the destination MAC address, the source IP
  address, the destination IP address, and the Ethernet protocol type
  field (although classification may take place on other fields, such
  as source and destination transport port numbers).  It is essential
  to increase the flow timeout time on a vSwitch before conducting any
  performance tests that do not intend to measure the flow setup time
  (see Section 3 of [RFC2889]).  Normally, the first packet of a
  particular stream will install the flow in the virtual switch, which
  introduces additional latency; subsequent packets of the same flow
  are not subject to this latency if the flow is already installed on
  the vSwitch.









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3.5.  Benchmarks Using Baselines with Resource Isolation

  This outline describes the measurement of baselines with isolated
  resources at a high level, which is the intended approach at this
  time.

  1.  Baselines:

      *  Optional: Benchmark platform forwarding capability without a
         vSwitch or VNF for at least 72 hours (serves as a means of
         platform validation and a means to obtain the base performance
         for the platform in terms of its maximum forwarding rate and
         latency).

                                                             __
         +--------------------------------------------------+   |
         |   +------------------------------------------+   |   |
         |   |                                          |   |   |
         |   |          Simple Forwarding App           |   |  Host
         |   |                                          |   |   |
         |   +------------------------------------------+   |   |
         |   |                 NIC                      |   |   |
         +---+------------------------------------------+---+ __|
                    ^                           :
                    |                           |
                    :                           v
         +--------------------------------------------------+
         |                                                  |
         |                Traffic Generator                 |
         |                                                  |
         +--------------------------------------------------+

           Figure 1: Benchmark Platform Forwarding Capability


















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      *  Benchmark VNF forwarding capability with direct connectivity
         (vSwitch bypass, e.g., SR/IOV) for at least 72 hours (serves
         as a means of VNF validation and a means to obtain the base
         performance for the VNF in terms of its maximum forwarding
         rate and latency).  The metrics gathered from this test will
         serve as a key comparison point for vSwitch bypass
         technologies performance and vSwitch performance.

                                                                  __
        +--------------------------------------------------+ __     |
        |   +------------------------------------------+   |   |    |
        |   |                                          |   | Host/  |
        |   |                 VNF                      |   | Guest  |
        |   |                                          |   |   |    |
        |   +------------------------------------------+   | __|    |
        |   |          Passthrough/SR-IOV              |   |       Host
        |   +------------------------------------------+   |        |
        |   |                 NIC                      |   |        |
        +---+------------------------------------------+---+      __|
                   ^                           :
                   |                           |
                   :                           v
        +--------------------------------------------------+
        |                                                  |
        |                Traffic Generator                 |
        |                                                  |
        +--------------------------------------------------+

              Figure 2: Benchmark VNF Forwarding Capability

      *  Benchmarking with isolated resources alone and with other
         resources (both hardware and software) disabled; for example,
         vSwitch and VM are SUT.

      *  Benchmarking with isolated resources alone, thus leaving some
         resources unused.

      *  Benchmarking with isolated resources and all resources
         occupied.

  2.  Next Steps:

      *  Limited sharing

      *  Production scenarios

      *  Stressful scenarios




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4.  VSPERF Specification Summary

  The overall specification in preparation is referred to as a Level
  Test Design (LTD) document, which will contain a suite of performance
  tests.  The base performance tests in the LTD are based on the
  pre-existing specifications developed by the BMWG to test the
  performance of physical switches.  These specifications include:

  o  Benchmarking Methodology for Network Interconnect Devices
     [RFC2544]

  o  Benchmarking Methodology for LAN Switching [RFC2889]

  o  Device Reset Characterization [RFC6201]

  o  Packet Delay Variation Applicability Statement [RFC5481]

  The two most recent RFCs above ([RFC6201] and [RFC5481]) are being
  applied in benchmarking for the first time and represent a
  development challenge for test equipment developers.  Fortunately,
  many members of the testing system community have engaged on the
  VSPERF project, including an open source test system.

  In addition to this, the LTD also reuses the terminology defined by:

  o  Benchmarking Terminology for LAN Switching Devices [RFC2285]

  It is recommended that these references be included in future
  benchmarking specifications:

  o  Methodology for IP Multicast Benchmarking [RFC3918]

  o  Packet Reordering Metrics [RFC4737]

  As one might expect, the most fundamental internetworking
  characteristics of throughput and latency remain important when the
  switch is virtualized, and these benchmarks figure prominently in the
  specification.

  When considering characteristics important to "telco" network
  functions, additional performance metrics are needed.  In this case,
  the project specifications have referenced metrics from the IETF IP
  Performance Metrics (IPPM) literature.  This means that the latency
  test described in [RFC2544] is replaced by measurement of a metric
  derived from IPPM's [RFC7679], where a set of statistical summaries
  will be provided (mean, max, min, and percentiles).  Further metrics
  planned to be benchmarked include packet delay variation as defined
  by [RFC5481], reordering, burst behaviour, DUT availability, DUT



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  capacity, and packet loss in long-term testing at the throughput
  level, where some low level of background loss may be present and
  characterized.

  Tests have been designed to collect the metrics below:

  o  Throughput tests are designed to measure the maximum forwarding
     rate (in frames per second, fps) and bit rate (in Mbps) for a
     constant load (as defined by [RFC1242]) without traffic loss.

  o  Packet and frame-delay distribution tests are designed to measure
     the average minimum and maximum packet (and/or frame) delay for
     constant loads.

  o  Packet delay tests are designed to understand latency distribution
     for different packet sizes and to uncover outliers over an
     extended test run.

  o  Scalability tests are designed to understand how the virtual
     switch performs with an increasing number of flows, number of
     active ports, configuration complexity of the forwarding logic,
     etc.

  o  Stream performance tests (with TCP or UDP) are designed to measure
     bulk data transfer performance, i.e., how fast systems can send
     and receive data through the switch.

  o  Control-path and data-path coupling tests are designed to
     understand how closely the data path and the control path are
     coupled, as well as the effect of this coupling on the performance
     of the DUT (for example, delay of the initial packet of a flow).

  o  CPU and memory consumption tests are designed to understand the
     virtual switch's footprint on the system and are conducted as
     auxiliary measurements with the benchmarks above.  They include
     CPU utilization, cache utilization, and memory footprint.

  o  The so-called "soak" tests, where the selected test is conducted
     over a long period of time (with an ideal duration of 24 hours but
     only long enough to determine that stability issues exist when
     found; there is no requirement to continue a test when a DUT
     exhibits instability over time).  The key performance
     characteristics and benchmarks for a DUT are determined (using
     short duration tests) prior to conducting soak tests.  The purpose
     of soak tests is to capture transient changes in performance,
     which may occur due to infrequent processes, memory leaks, or the
     low-probability coincidence of two or more processes.  The
     stability of the DUT is the paramount consideration, so



Tahhan, et al.                Informational                    [Page 12]

RFC 8204                 Benchmarking vSwitches           September 2017


     performance must be evaluated periodically during continuous
     testing, and this results in use of frame rate metrics [RFC2889]
     instead of throughput [RFC2544] (which requires stopping traffic
     to allow time for all traffic to exit internal queues), for
     example.

  Additional test specification development should include:

  o  Request/response performance tests (with TCP or UDP), which
     measure the transaction rate through the switch.

  o  Noisy neighbor tests, in order to understand the effects of
     resource sharing on the performance of a virtual switch.

  o  Tests derived from examination of ETSI NFV Draft GS IFA003
     requirements [IFA003] on characterization of acceleration
     technologies applied to vSwitches.

  The flexibility of deployment of a virtual switch within a network
  means that it is necessary to characterize the performance of a
  vSwitch in various deployment scenarios.  The deployment scenarios
  under consideration are shown in the following figures:

                                                        __
    +--------------------------------------------------+   |
    |              +--------------------+              |   |
    |              |                    |              |   |
    |              |                    v              |   |  Host
    |   +--------------+            +--------------+   |   |
    |   |   PHY Port   |  vSwitch   |   PHY Port   |   |   |
    +---+--------------+------------+--------------+---+ __|
               ^                           :
               |                           |
               :                           v
    +--------------------------------------------------+
    |                                                  |
    |                Traffic Generator                 |
    |                                                  |
    +--------------------------------------------------+

       Figure 3: Physical Port to Virtual Switch to Physical Port










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                                                        __
    +---------------------------------------------------+   |
    |                                                   |   |
    |   +-------------------------------------------+   |   |
    |   |                 Application               |   |   |
    |   +-------------------------------------------+   |   |
    |       ^                                  :        |   |
    |       |                                  |        |   |  Guest
    |       :                                  v        |   |
    |   +---------------+           +---------------+   |   |
    |   | Logical Port 0|           | Logical Port 1|   |   |
    +---+---------------+-----------+---------------+---+ __|
            ^                                  :
            |                                  |
            :                                  v         __
    +---+---------------+----------+---------------+---+   |
    |   | Logical Port 0|          | Logical Port 1|   |   |
    |   +---------------+          +---------------+   |   |
    |       ^                                  :       |   |
    |       |                                  |       |   |  Host
    |       :                                  v       |   |
    |   +--------------+            +--------------+   |   |
    |   |   PHY Port   |  vSwitch   |   PHY Port   |   |   |
    +---+--------------+------------+--------------+---+ __|
               ^                           :
               |                           |
               :                           v
    +--------------------------------------------------+
    |                                                  |
    |                Traffic Generator                 |
    |                                                  |
    +--------------------------------------------------+

  Figure 4: Physical Port to Virtual Switch to VNF to Virtual Switch to
                              Physical Port
















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                                                     __
    +----------------------+  +----------------------+  |
    |   Guest 1            |  |   Guest 2            |  |
    |   +---------------+  |  |   +---------------+  |  |
    |   |  Application  |  |  |   |  Application  |  |  |
    |   +---------------+  |  |   +---------------+  |  |
    |       ^       |      |  |       ^       |      |  |
    |       |       v      |  |       |       v      |  |  Guests
    |   +---------------+  |  |   +---------------+  |  |
    |   | Logical Ports |  |  |   | Logical Ports |  |  |
    |   |   0       1   |  |  |   |   0       1   |  |  |
    +---+---------------+--+  +---+---------------+--+__|
            ^       :                 ^       :
            |       |                 |       |
            :       v                 :       v       _
    +---+---------------+---------+---------------+--+ |
    |   |   0       1   |         |   3       4   |  | |
    |   | Logical Ports |         | Logical Ports |  | |
    |   +---------------+         +---------------+  | |
    |       ^       |                 ^       |      | |  Host
    |       |       \-----------------/       v      | |
    |   +--------------+          +--------------+   | |
    |   |   PHY Ports  | vSwitch  |   PHY Ports  |   | |
    +---+--------------+----------+--------------+---+_|
            ^                                 :
            |                                 |
            :                                 v
    +--------------------------------------------------+
    |                                                  |
    |                Traffic Generator                 |
    |                                                  |
    +--------------------------------------------------+

  Figure 5: Physical Port to Virtual Switch to VNF to Virtual Switch to
                 VNF to Virtual Switch to Physical Port
















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                                                         __
    +---------------------------------------------------+   |
    |                                                   |   |
    |   +-------------------------------------------+   |   |
    |   |                 Application               |   |   |
    |   +-------------------------------------------+   |   |
    |       ^                                           |   |
    |       |                                           |   |  Guest
    |       :                                           |   |
    |   +---------------+                               |   |
    |   | Logical Port 0|                               |   |
    +---+---------------+-------------------------------+ __|
            ^
            |
            :                                            __
    +---+---------------+------------------------------+   |
    |   | Logical Port 0|                              |   |
    |   +---------------+                              |   |
    |       ^                                          |   |
    |       |                                          |   |  Host
    |       :                                          |   |
    |   +--------------+                               |   |
    |   |   PHY Port   |  vSwitch                      |   |
    +---+--------------+------------ -------------- ---+ __|
               ^
               |
               :
    +--------------------------------------------------+
    |                                                  |
    |                Traffic Generator                 |
    |                                                  |
    +--------------------------------------------------+

            Figure 6: Physical Port to Virtual Switch to VNF

















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RFC 8204                 Benchmarking vSwitches           September 2017


                                                         __
    +---------------------------------------------------+   |
    |                                                   |   |
    |   +-------------------------------------------+   |   |
    |   |                 Application               |   |   |
    |   +-------------------------------------------+   |   |
    |                                          :        |   |
    |                                          |        |   |  Guest
    |                                          v        |   |
    |                               +---------------+   |   |
    |                               | Logical Port  |   |   |
    +-------------------------------+---------------+---+ __|
                                               :
                                               |
                                               v         __
    +------------------------------+---------------+---+   |
    |                              | Logical Port  |   |   |
    |                              +---------------+   |   |
    |                                          :       |   |
    |                                          |       |   |  Host
    |                                          v       |   |
    |                               +--------------+   |   |
    |                     vSwitch   |   PHY Port   |   |   |
    +-------------------------------+--------------+---+ __|
                                           :
                                           |
                                           v
    +--------------------------------------------------+
    |                                                  |
    |                Traffic Generator                 |
    |                                                  |
    +--------------------------------------------------+

            Figure 7: VNF to Virtual Switch to Physical Port

















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RFC 8204                 Benchmarking vSwitches           September 2017


                                                     __
    +----------------------+  +----------------------+  |
    |   Guest 1            |  |   Guest 2            |  |
    |   +---------------+  |  |   +---------------+  |  |
    |   |  Application  |  |  |   |  Application  |  |  |
    |   +---------------+  |  |   +---------------+  |  |
    |              |       |  |       ^              |  |
    |              v       |  |       |              |  |  Guests
    |   +---------------+  |  |   +---------------+  |  |
    |   | Logical Ports |  |  |   | Logical Ports |  |  |
    |   |           0   |  |  |   |   0           |  |  |
    +---+---------------+--+  +---+---------------+--+__|
                    :                 ^
                    |                 |
                    v                 :               _
    +---+---------------+---------+---------------+--+ |
    |   |           1   |         |   1           |  | |
    |   | Logical Ports |         | Logical Ports |  | |
    |   +---------------+         +---------------+  | |
    |               |                 ^              | |  Host
    |               \-----------------/              | |
    |                                                | |
    |                    vSwitch                     | |
    +------------------------------------------------+_|

                 Figure 8: VNF to Virtual Switch to VNF

  A set of deployment scenario figures is available on the VSPERF "Test
  Methodology" wiki page [TestTopo].

5.  3x3 Matrix Coverage

  This section organizes the many existing test specifications into the
  "3x3" matrix (introduced in [RFC8172]).  Because the LTD
  specification ID names are quite long, this section is organized into
  lists for each occupied cell of the matrix (not all are occupied;
  also, the matrix has grown to 3x4 to accommodate scale metrics when
  displaying the coverage of many metrics/benchmarks).  The current
  version of the LTD specification is available; see [LTD].

  The tests listed below assess the activation of paths in the data
  plane rather than the control plane.

  A complete list of tests with short summaries is available on the
  VSPERF "LTD Test Spec Overview" wiki page [LTDoverV].






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5.1.  Speed of Activation

  o  Activation.RFC2889.AddressLearningRate

  o  PacketLatency.InitialPacketProcessingLatency

5.2.  Accuracy of Activation

  o  CPDP.Coupling.Flow.Addition

5.3.  Reliability of Activation

  o  Throughput.RFC2544.SystemRecoveryTime

  o  Throughput.RFC2544.ResetTime

5.4.  Scale of Activation

  o  Activation.RFC2889.AddressCachingCapacity

5.5.  Speed of Operation

  o  Throughput.RFC2544.PacketLossRate

  o  Stress.RFC2544.0PacketLoss

  o  Throughput.RFC2544.PacketLossRateFrameModification

  o  Throughput.RFC2544.BackToBackFrames

  o  Throughput.RFC2889.MaxForwardingRate

  o  Throughput.RFC2889.ForwardPressure

  o  Throughput.RFC2889.BroadcastFrameForwarding

  o  Throughput.RFC2544.WorstN-BestN

  o  Throughput.Overlay.Network.<tech>.RFC2544.PacketLossRatio

5.6.  Accuracy of Operation

  o  Throughput.RFC2889.ErrorFramesFiltering

  o  Throughput.RFC2544.Profile






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5.7.  Reliability of Operation

  o  Throughput.RFC2889.Soak

  o  Throughput.RFC2889.SoakFrameModification

  o  PacketDelayVariation.RFC3393.Soak

5.8.  Scalability of Operation

  o  Scalability.RFC2544.0PacketLoss

  o  MemoryBandwidth.RFC2544.0PacketLoss.Scalability

  o  Scalability.VNF.RFC2544.PacketLossProfile

  o  Scalability.VNF.RFC2544.PacketLossRatio

5.9.  Summary

|---------------------------------------------------------------------|
|              |           |            |               |             |
|              |   SPEED   |  ACCURACY  |  RELIABILITY  |    SCALE    |
|              |           |            |               |             |
|---------------------------------------------------------------------|
|              |           |            |               |             |
|  Activation  |     X     |     X      |       X       |      X      |
|              |           |            |               |             |
|---------------------------------------------------------------------|
|              |           |            |               |             |
|  Operation   |     X     |     X      |       X       |      X      |
|              |           |            |               |             |
|---------------------------------------------------------------------|
|              |           |            |               |             |
| De-activation|           |            |               |             |
|              |           |            |               |             |
|---------------------------------------------------------------------|














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6.  Security Considerations

  Benchmarking activities as described in this memo are limited to
  technology characterization of a Device Under Test/System Under Test
  (DUT/SUT) using controlled stimuli in a laboratory environment with
  dedicated address space and the constraints specified in the sections
  above.

  The benchmarking network topology will be an independent test setup
  and MUST NOT be connected to devices that may forward the test
  traffic into a production network or misroute traffic to the test
  management network.

  Further, benchmarking is performed on a "black-box" basis and relies
  solely on measurements observable external to the DUT/SUT.

  Special capabilities SHOULD NOT exist in the DUT/SUT specifically for
  benchmarking purposes.  Any implications for network security arising
  from the DUT/SUT SHOULD be identical in the lab and in production
  networks.

7.  References

7.1.  Normative References

  [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
             Requirement Levels", BCP 14, RFC 2119,
             DOI 10.17487/RFC2119, March 1997,
             <https://www.rfc-editor.org/info/rfc2119>.

  [RFC2285]  Mandeville, R., "Benchmarking Terminology for LAN
             Switching Devices", RFC 2285, DOI 10.17487/RFC2285,
             February 1998, <https://www.rfc-editor.org/info/rfc2285>.

  [RFC2544]  Bradner, S. and J. McQuaid, "Benchmarking Methodology for
             Network Interconnect Devices", RFC 2544,
             DOI 10.17487/RFC2544, March 1999,
             <https://www.rfc-editor.org/info/rfc2544>.

  [RFC2889]  Mandeville, R. and J. Perser, "Benchmarking Methodology
             for LAN Switching Devices", RFC 2889,
             DOI 10.17487/RFC2889, August 2000,
             <https://www.rfc-editor.org/info/rfc2889>.

  [RFC3918]  Stopp, D. and B. Hickman, "Methodology for IP Multicast
             Benchmarking", RFC 3918, DOI 10.17487/RFC3918, October
             2004, <https://www.rfc-editor.org/info/rfc3918>.




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  [RFC4737]  Morton, A., Ciavattone, L., Ramachandran, G., Shalunov,
             S., and J. Perser, "Packet Reordering Metrics", RFC 4737,
             DOI 10.17487/RFC4737, November 2006,
             <https://www.rfc-editor.org/info/rfc4737>.

  [RFC6201]  Asati, R., Pignataro, C., Calabria, F., and C. Olvera,
             "Device Reset Characterization", RFC 6201,
             DOI 10.17487/RFC6201, March 2011,
             <https://www.rfc-editor.org/info/rfc6201>.

  [RFC6985]  Morton, A., "IMIX Genome: Specification of Variable Packet
             Sizes for Additional Testing", RFC 6985,
             DOI 10.17487/RFC6985, July 2013,
             <https://www.rfc-editor.org/info/rfc6985>.

  [RFC7679]  Almes, G., Kalidindi, S., Zekauskas, M., and A. Morton,
             Ed., "A One-Way Delay Metric for IP Performance Metrics
             (IPPM)", STD 81, RFC 7679, DOI 10.17487/RFC7679, January
             2016, <https://www.rfc-editor.org/info/rfc7679>.

  [RFC8174]  Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
             2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
             May 2017, <https://www.rfc-editor.org/info/rfc8174>.

7.2.  Informative References

  [BENCHMARK-METHOD]
             Huang, L., Ed., Rong, G., Ed., Mandeville, B., and B.
             Hickman, "Benchmarking Methodology for Virtualization
             Network Performance", Work in Progress, draft-huang-bmwg-
             virtual-network-performance-03, July 2017.

  [DanubeRel]
             OPNFV, "Danube",
             <https://wiki.opnfv.org/display/SWREL/Danube>.

  [IEEE802.1ac]
             IEEE, "IEEE Standard for Local and metropolitan area
             networks -- Media Access Control (MAC) Service
             Definition", IEEE 802.1AC-2016,
             DOI 10.1109/IEEESTD.2017.7875381, 2016,
             <https://standards.ieee.org/findstds/
             standard/802.1AC-2016.html>.

  [IEEE829]  IEEE, "IEEE Standard for Software and System Test
             Documentation", IEEE 829-2008,
             DOI 10.1109/IEEESTD.2008.4578383,
             <http://ieeexplore.ieee.org/document/4578383/>.



Tahhan, et al.                Informational                    [Page 22]

RFC 8204                 Benchmarking vSwitches           September 2017


  [IFA003]   ETSI, "Network Functions Virtualisation (NFV);
             Acceleration Technologies; vSwitch Benchmarking and
             Acceleration Specification", ETSI GS NFV-IFA 003 V2.1.1,
             April 2016, <http://www.etsi.org/deliver/etsi_gs/
             NFV-IFA/001_099/003/02.01.01_60/
             gs_NFV-IFA003v020101p.pdf>.

  [LTD]      Tahhan, M., "VSPERF Level Test Design (LTD)",
             <http://docs.opnfv.org/en/stable-danube/
             submodules/vswitchperf/docs/testing/developer/
             requirements/vswitchperf_ltd.html#>.

  [LTDoverV] Morton, A., "LTD Test Spec Overview",
             <https://wiki.opnfv.org/display/vsperf/
             LTD+Test+Spec+Overview>.

  [OPNFV]    OPNFV, "OPNFV", <https://www.opnfv.org/>.

  [RFC1242]  Bradner, S., "Benchmarking Terminology for Network
             Interconnection Devices", RFC 1242, DOI 10.17487/RFC1242,
             July 1991, <https://www.rfc-editor.org/info/rfc1242>.

  [RFC5481]  Morton, A. and B. Claise, "Packet Delay Variation
             Applicability Statement", RFC 5481, DOI 10.17487/RFC5481,
             March 2009, <https://www.rfc-editor.org/info/rfc5481>.

  [RFC8172]  Morton, A., "Considerations for Benchmarking Virtual
             Network Functions and Their Infrastructure", RFC 8172,
             DOI 10.17487/RFC8172, July 2017,
             <https://www.rfc-editor.org/info/rfc8172>.

  [TestTopo] Snyder, E., "Test Methodology",
             <https://wiki.opnfv.org/display/vsperf/Test+Methodology>.

  [VSPERFhome]
             Tahhan, M., "VSPERF Home",
             <https://wiki.opnfv.org/display/vsperf/VSperf+Home>.

Acknowledgements

  The authors appreciate and acknowledge comments from Scott Bradner,
  Marius Georgescu, Ramki Krishnan, Doug Montgomery, Martin Klozik,
  Christian Trautman, Benoit Claise, and others for their reviews.

  We also acknowledge the early work in [BENCHMARK-METHOD] and useful
  discussion with the authors.





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RFC 8204                 Benchmarking vSwitches           September 2017


Authors' Addresses

  Maryam Tahhan
  Intel

  Email: [email protected]


  Billy O'Mahony
  Intel

  Email: [email protected]


  Al Morton
  AT&T Labs
  200 Laurel Avenue South
  Middletown, NJ  07748
  United States of America

  Phone: +1 732 420 1571
  Fax:   +1 732 368 1192
  Email: [email protected]




























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