:Use Pktgen to test the network performance of ECS instances

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Overview

This topic describes how to use Pktgen to test the network performance of Elastic Compute Service (ECS) instances.

Background information

Take note of the following items:

• Before you perform risky operations such as modifying instance configurations or data, we recommend that you check the disaster recovery and fault tolerance capabilities of the instances to ensure data security.
• You can modify the configurations and data of instances including ECS and ApsaraDB RDS instances. We recommend that before you modify instance configurations or data, you create snapshots or enable RDS log backup.
• If you have authorized or submitted sensitive information such as the logon account and password in the Alibaba Cloud Management Console, we recommend that you modify these information in a timely manner.

The following steps describe how to use Pktgen to test the network performance of ECS instances:

Step 1: Prepare the environment

Prepare two ECS instances, one for the generator and the other for the receiver. Prepare two network interface controllers (NICs), one for logon and the other for testing. Make sure that the two NICs can communicate with each other. Then, run the ifconfig command and record the IP addresses and media access control (MAC) addresses of the two NICs, which are required when you configure traffic.

Step 2: Install software

Perform the following operations on both the generator and the receiver:

1. Log on to a Linux instance. For more information about how to log on to the Linux instance, see Connect to a Linux instance by using a username and password.
2. Run the following command to create the pktgen directory:

   mkdir pktgen

3. Run the following command to go to the pktgen directory:

   cd pktgen

4. Run the following command to download the installation packages of Pktgen, Lua, and Data Plane Development Kit (DPDK):

   wget https://git.dpdk.org/apps/pktgen-dpdk/snapshot/pktgen-dpdk-pktgen-3.6.5.zip https://www.lua.org/ftp/lua-5.4.3.tar.gz https://fast.dpdk.org/rel/dpdk-18.11.11.tar.xz

   Note: The versions of Pktgen, Lua, and DPDK must be compatible with each other. Otherwise, compilation errors may occur. In this topic, the versions in the preceding command are used. Before you use the installation packages of other versions, make sure that the versions are compatible with each other.

5. Run the following commands in sequence to decompress the installation packages of Pktgen, Lua, and DPDK:

   tar -Jxvf dpdk-18.11.11.tar.xz
   
   tar -zxvf lua-5.4.3.tar.gz
   
   unzip pktgen-dpdk-pktgen-3.6.5.zip

6. If some dependencies are missing during the compilation process, run the following commands to install the corresponding installation packages:
   • CentOS 7
     

     yum -y install kernel-devel.x86_64
     yum -y install numactl-devel.x86_64
     yum -y install elfutils-libelf-devel
     yum -y install libpcap-devel

   • CentOS 8

     Note: By default, libpcap-devel is not installed on the CentOS 8 operating system. Run the following commands to install libpcap-devel:

     dnf config-manager --add-repo /etc/yum.repos.d/CentOS-PowerTools.repo 
     dnf config-manager --set-enabled PowerTools 
     dnf install epel-release 
     dnf install libpcap-devel

7. Run the following commands in sequence to compile and install Pktgen:
   

   cd dpdk-stable-18.11.11
   make config T=x86_64-native-linuxapp-gcc 
   make all -j32

8. Run the following commands in sequence to compile and install Lua:
   

   cd lua-5.4.3
   make
   make install

9. Run the following commands in sequence to compile and install DPDK:
   

   cd pktgen-dpdk-pktgen-3.6.5/
    export RTE_SDK=/root/pktgen/dpdk-stable-18.11.11/
   export RTE_TARGET=build 
   make -j32

Step 3: Bind drivers to VFIO

Perform the following operations on both the generator and the receiver:

1. View the /proc/cmdline file and check whether the line starting with BOOT_IMAGE contains the intel_iommu=on parameter. If the line does not contain the intel_iommu=on parameter, edit the /etc/default/grub file, add the intel_iommu=on parameter to the line starting with GRUB_CMDLINE_LINUX, and then restart the ECS instances.
2. Run the following commands in sequence to install the Virtual Function I/O (VFIO) and VFIO-PCI drivers:

   modprobe vfio
   
   modprobe vfio-pci

3. Run the following command to configure noniommu_mode:

   echo 1 > /sys/module/vfio/parameters/enable_unsafe_noiommu_mode

4. Run the following command to check and record the bus-info value of the NIC:

   ethtool -i eth1

   Note: In this topic, the eth1 NIC is used. In actual operations, replace eth1 with your NIC.

   A command output similar to the following one is returned:

   driver: virtio_net
   
   
   version: 1.0.0
   
   
   firmware-version:
   
   
   expansion-rom-version:
   
   bus-info: 0000:00:08.0
   
   supports-statistics: no
   
   supports-test: no
   
   supports-eeprom-access: no
   
   supports-register-dump: no
   
   supports-priv-flags: no

5. Run the following command to unbind the virtio driver from eth1.

   echo "[$Bus-info]" > /sys/bus/pci/drivers/virtio-pci/unbind

   Note: [$Bus-info] is the bus-info value of the NIC obtained in the previous step.

6. Run the following command to bind bus-info to the VFIO-PCI driver:

   /root/pktgen/dpdk-stable-18.11.11/usertools/dpdk-devbind.py -b vfio-pci [$Bus-info]

Step 4: Configure Hugepages

Perform the following operations on both the generator and the receiver. Check the number of your nodes and run the corresponding commands:

• Dual nodes

  echo 8000 > /sys/devices/system/node/node1/hugepages/hugepages-2048kB/nr_hugepages
  echo 8000 > /sys/devices/system/node/node0/hugepages/hugepages-2048kB/nr_hugepages

• Single node

  echo 8000 > /sys/kernel/mm/hugepages/hugepages-2048kB/nr_hugepages

Step 5: Start Pktgen

Perform the following operations on both the generator and the receiver:

Application scope

• ECS