Enabling NIC Multi-Queue

Scenarios

With the increase of network I/O bandwidth, single-core CPUs face bottlenecks in handling network interrupts. NIC multi-queue assigns interrupts to different CPUs for higher packets per second (PPS) and bandwidth.

Support of NIC Multi-Queue

NIC multi-queue can be enabled on an ECS only when the ECS specifications, virtualization type, and image OS meet the requirements described in this section.

• For details about the ECS specifications that support NIC multi-queue, see ECS Types.
  

  If the number of NIC queues is greater than 1, NIC multi-queue is supported.

• The virtualization type must be KVM.
• The Linux public images listed in Table 2 support NIC multi-queue.
  

  • The PV driver of a Windows ECS dynamically adjusts the number of NIC queues based on the number of vCPUs of the ECS, and you do not need to set the number of Windows NIC multi-queues.
  • Public images that contain Windows Server 2008 are no longer available. However, you can still use private images that contain Windows Server 2008.
  • It is a good practice to upgrade the kernel version of the Linux ECS to 2.6.35 or later. Otherwise, NIC multi-queue is not supported.

    Run the uname -r command to obtain the kernel version. If the kernel version is earlier than 2.6.35, contact customer service to upgrade the kernel.

Importing the External Image File to the IMS Console

Setting NIC Multi-Queue for the Image

Windows OSs have not commercially supported NIC multi-queue. If you enable NIC multi-queue in a Windows image, starting an ECS created using such an image may be slow.

Use one of the following methods to set the NIC multi-queue attribute:

Method 3: Add hw_vif_multiqueue_enabled to an image through the API.

1. For instructions about how to obtain the token, see Authentication.
2. For instructions about how to call an API to update image information, see Updating Image Information (Native OpenStack API).
3. Add X-Auth-Token to the request header.

   The value of X-Auth-Token is the token obtained in step 1.

4. Add Content-Type to the request header.

   The value of Content-Type is application/openstack-images-v2.1-json-patch.

   The request URI is in the following format:

   PATCH /v2/images/{image_id}

   The request body is as follows:

   [       
            { 
             "op":"add",
             "path":"/hw_vif_multiqueue_enabled", 
             "value": "true" 
            } 
    ]

   Figure 1 shows an example request body for modifying the NIC multi-queue attribute.

   Figure 1 Example request body
   

Creating an ECS Using a Private Image

Running the Script for Configuring NIC Multi-Queue

The PV driver of a Windows ECS dynamically adjusts the number of NIC queues based on the number of vCPUs of the ECS, and you do not need to set the number of Windows NIC multi-queues.

A script for automatically enabling NIC multi-queue on a Linux ECS is available. After the script is configured, the ECS supports NIC multi-queue.

The script for automatically enabling NIC multi-queue only supports eth0 NICs.

1. Log in to the ECS and run the following command to check the number of queues supported by and enabled for a NIC:

   ethtool -l NIC

   Example output:

   [root@localhost ~]# ethtool -l eth0   # Number of queues used by NIC eth0
   Channel parameters for eth0:
   Pre-set maximums:
   RX:               0
   TX:               0
   Other:            0
   Combined:         4   # The NIC supports a maximum of four queues.
   Current hardware settings:
   RX:               0
   TX:               0
   Other:            0
   Combined:         1   # One queue has been enabled for the NIC.

   If the values of the two Combined fields are the same, NIC multi-queue has been enabled. No further action is required.

2. Run the following command to download the configuration script "multi-queue-hw":

   wget URL to download the script

   URL: https://ecs-instance-driver.obs.cn-north-1.myhuaweicloud.com/multi-queue-hw

3. Run the following command to assign execution permissions to the script:

   chmod +x multi-queue-hw

4. Run the following command to move the multi-queue-hw script to the /etc/init.d directory:

   mv multi-queue-hw /etc/init.d

5. Run the following command to run the script:

   /etc/init.d/multi-queue-hw start

   The script takes effect immediately after being executed. However, after the ECS is stopped, NIC multi-queue disables automatically.

6. Add startup configuration for each OS so that NIC multi-queue automatically enables upon the ECS startup.
   • For CentOS, Red Hat, Fedora, EulerOS, SUSE, and OpenSUSE, run the following command:

     chkconfig multi-queue-hw on

   • For Ubuntu, run the following command:

     update-rc.d multi-queue-hw defaults 90 10

   • For Debian, run the following command:

     systemctl enable multi-queue-hw

Viewing the Number of Queues of the NIC

Example:

[root@localhost ~]# ethtool -l eth0  #View the number of queues used by NIC eth0.
Channel parameters for eth0:
Pre-set maximums:
RX:               0
TX:               0
Other:                  0
Combined: 4  #Indicates that a maximum of four queues can be enabled for the NIC.
Current hardware settings:
RX:               0
TX:               0
Other:                  0
Combined: 1 #Indicates that four queues have been enabled.