1. Getting Started with ‘vsperf’

1.1. Hardware Requirements

VSPERF requires one of the following traffic generators to run tests:

  • IXIA traffic generator (IxNetwork hardware) and a machine that runs the IXIA client software
  • Spirent traffic generator (TestCenter hardware chassis or TestCenter virtual in a VM) and a

VM to run the Spirent Virtual Deployment Service image, formerly known as “Spirent LabServer”.

Both test configurations, above, also require a CentOS Linux release 7.1.1503 (Core) host.

1.2. vSwitch Requirements

The vSwitch must support Open Flow 1.3 or greater.

1.3. Installation

Follow the installation instructions to install.

1.4. IXIA Setup

1.4.1. On the CentOS 7 system

You need to install IxNetworkTclClient$(VER_NUM)Linux.bin.tgz.

1.4.2. On the IXIA client software system

Find the IxNetwork TCL server app (start -> All Programs -> IXIA -> IxNetwork -> IxNetwork_$(VER_NUM) -> IxNetwork TCL Server)

Right click on IxNetwork TCL Server, select properties - Under shortcut tab in the Target dialogue box make sure there is the argument “-tclport xxxx” where xxxx is your port number (take note of this port number you will need it for the 10_custom.conf file).

Alt text

Hit Ok and start the TCL server application

1.5. Spirent Setup

Spirent installation files and instructions are available on the Spirent support website at:


Select a version of Spirent TestCenter software to utilize. This example will use Spirent TestCenter v4.57 as an example. Substitute the appropriate version in place of ‘v4.57’ in the examples, below.

1.5.1. On the CentOS 7 System

Download and install the following:

Spirent TestCenter Application, v4.57 for 64-bit Linux Client

1.5.2. Spirent Virtual Deployment Service (VDS)

Spirent VDS is required for both TestCenter hardware and virtual chassis in the vsperf environment. For installation, select the version that matches the Spirent TestCenter Application version. For v4.57, the matching VDS version is 1.0.55. Download either the ova (VMware) or qcow2 (QEMU) image and create a VM with it. Initialize the VM according to Spirent installation instructions.

1.5.3. Using Spirent TestCenter Virtual (STCv)

STCv is available in both ova (VMware) and qcow2 (QEMU) formats. For VMware, download:

Spirent TestCenter Virtual Machine for VMware, v4.57 for Hypervisor - VMware ESX.ESXi

Virtual test port performance is affected by the hypervisor configuration. For best practice results in deploying STCv, the following is suggested:

  • Create a single VM with two test ports rather than two VMs with one port each
  • Set STCv in DPDK mode
  • Give STCv 2*n + 1 cores, where n = the number of ports. For vsperf, cores = 5.
  • Turning off hyperthreading and pinning these cores will improve performance
  • Give STCv 2 GB of RAM

To get the highest performance and accuracy, Spirent TestCenter hardware is recommended. vsperf can run with either stype test ports.

1.6. Cloning and building src dependencies

In order to run VSPERF, you will need to download DPDK and OVS. You can do this manually and build them in a preferred location, or you could use vswitchperf/src. The vswitchperf/src directory contains makefiles that will allow you to clone and build the libraries that VSPERF depends on, such as DPDK and OVS. To clone and build simply:

cd src

VSPERF can be used with OVS without DPDK support. In this case you have to specify path to the kernel sources by WITH_LINUX parameter:

cd src
make WITH_LINUX=/lib/modules/`uname -r`/build

To build DPDK and OVS for PVP and PVVP testing with vhost_user as the guest access method, use:


To delete a src subdirectory and its contents to allow you to re-clone simply use:

make clobber

1.7. Configure the ./conf/10_custom.conf file

The supplied 10_custom.conf file must be modified, as it contains configuration items for which there are no reasonable default values.

The configuration items that can be added is not limited to the initial contents. Any configuration item mentioned in any .conf file in ./conf directory can be added and that item will be overridden by the custom configuration value.

1.8. Using a custom settings file

Alternatively a custom settings file can be passed to vsperf via the --conf-file argument.

./vsperf --conf-file <path_to_settings_py> ...

Note that configuration passed in via the environment (--load-env) or via another command line argument will override both the default and your custom configuration files. This “priority hierarchy” can be described like so (1 = max priority):

  1. Command line arguments
  2. Environment variables
  3. Configuration file(s)

1.9. Executing tests

Before running any tests make sure you have root permissions by adding the following line to /etc/sudoers:

username ALL=(ALL)       NOPASSWD: ALL

username in the example above should be replaced with a real username.

To list the available tests:

./vsperf --list-tests

To run a group of tests, for example all tests with a name containing ‘RFC2544’:

./vsperf --conf-file=user_settings.py --tests="RFC2544"

To run all tests:

./vsperf --conf-file=user_settings.py

Some tests allow for configurable parameters, including test duration (in seconds) as well as packet sizes (in bytes).

./vsperf --conf-file user_settings.py
    --tests RFC2544Tput
    --test-param "rfc2544_duration=10;packet_sizes=128"

For all available options, check out the help dialog:

./vsperf --help

1.10. Executing PVP and PVVP tests

To run tests using vhost-user as guest access method:

  1. Set VHOST_METHOD and VNF of your settings file to:
VNF = 'QemuDpdkVhost'
  1. Recompile src for VHOST USER testing
cd src
make cleanse
  1. Run test:
./vsperf --conf-file <path_to_settings_py>

To run tests using vhost-cuse as guest access method:

  1. Set VHOST_METHOD and VNF of your settings file to:
VNF = 'QemuDpdkVhostCuse'
  1. Recompile src for VHOST USER testing
cd src
make cleanse
  1. Run test:
./vsperf --conf-file <path_to_settings_py>

1.11. Executing PVP tests using Vanilla OVS

To run tests using Vanilla OVS:

  1. Set the following variables:
VSWITCH = 'OvsVanilla'
VNF = 'QemuVirtioNet'

VANILLA_TGEN_PORT1_MAC = nn:nn:nn:nn:nn:nn

VANILLA_TGEN_PORT2_MAC = nn:nn:nn:nn:nn:nn


or use --test-param

./vsperf --conf-file user_settings.py
         --test-param "vanilla_tgen_tx_ip=n.n.n.n;
  1. Recompile src for Vanilla OVS testing
cd src
make cleanse
make WITH_LINUX=/lib/modules/`uname -r`/build
  1. Run test:
./vsperf --conf-file <path_to_settings_py>

1.12. Code change verification by pylint

Every developer participating in VSPERF project should run pylint before his python code is submitted for review. Project specific configuration for pylint is available at ‘pylint.rc’.

Example of manual pylint invocation:

pylint --rcfile ./pylintrc ./vsperf

1.13. GOTCHAs:

1.13.1. OVS with DPDK and QEMU

If you encounter the following error: “before (last 100 chars): ‘-path=/dev/hugepages,share=on: unable to map backing store for hugepages: Cannot allocate memoryrnrn” with the PVP or PVVP deployment scenario, check the amount of hugepages on your system:

cat /proc/meminfo | grep HugePages

By default the vswitchd is launched with 1Gb of memory, to change this, modify –socket-mem parameter in conf/02_vswitch.conf to allocate an appropriate amount of memory:

VSWITCHD_DPDK_ARGS = ['-c', '0x4', '-n', '4', '--socket-mem 1024,0']