红帽全球峰会第 15 章 Configuring ethtool settings in NetworkManager connection profiles
NetworkManager can configure certain network driver and hardware settings persistently. Compared to using the ethtool utility to manage these settings, this has the benefit of not losing the settings after a reboot.
You can set the following ethtool settings in NetworkManager connection profiles:
- Offload features
- Network interface controllers can use the TCP offload engine (TOE) to offload processing certain operations to the network controller. This improves the network throughput.
- Interrupt coalesce settings
- By using interrupt coalescing, the system collects network packets and generates a single interrupt for multiple packets. This increases the amount of data sent to the kernel with one hardware interrupt, which reduces the interrupt load, and maximizes the throughput.
- Ring buffers
- These buffers store incoming and outgoing network packets. You can increase the ring buffer sizes to reduce a high packet drop rate.
- Channel settings
A network interface manages its associated number of channels along with hardware settings and network drivers. All devices associated with a network interface communicate with each other through interrupt requests (IRQ). Each device queue holds pending IRQ and communicates with each other over a data line known as channel. Types of queues are associated with specific channel types. These channel types include:
-
rxfor receiving queues -
txfor transmit queues -
otherfor link interrupts or single root input/output virtualization (SR-IOV) coordination -
combinedfor hardware capacity-based multipurpose channels
-
You can use NetworkManager to enable and disable ethtool offload features in a connection profile.
Procedure
For example, to enable the RX offload feature and disable TX offload in the
enp1s0connection profile, enter:# nmcli con modify enp1s0 ethtool.feature-rx on ethtool.feature-tx offThis command explicitly enables RX offload and disables TX offload.
For a list of settings you can configure, see the
ethtool settingsection in thenm-settings-nmcli(5)man page on your system.To remove the setting of an offload feature that you previously enabled or disabled, set the feature’s parameter to a null value. For example, to remove the configuration for TX offload, enter:
# nmcli con modify enp1s0 ethtool.feature-tx ""Reactivate the network profile:
# nmcli connection up enp1s0
Verification
Use the
ethtool -kcommand to display the current offload features of a network device:# ethtool -k network_device
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