Intel® Ethernet Adapters and Devices User Guide
Flow Control
This feature enables adapters to more effectively regulate traffic. Adapters generate flow control frames when their receive queues reach a pre-defined limit. Generating flow control frames signals the transmitter to slow transmission. Adapters respond to flow control frames by pausing packet transmission for the time specified in the flow control frame.
By enabling adapters to adjust packet transmission, flow control helps prevent dropped packets. You may improve RDMA performance by enabling flow control on all nodes and on the switch to which they connect.
For adapters to benefit from this feature, link partners must support flow control frames.
On systems running a Microsoft Windows Server* operating system, enabling QoS/priority flow control will disable link level flow control.
Some devices support Auto Negotiation. Selecting this will cause the device to advertise the value stored in its NVM (usually “Disabled”).
To change this setting in Intel® PROSet:
This setting is found on the PROset tab of the device’s Device Manager property sheet or in the Intel® PROSet Adapter Configuration Utility (Intel® PROSet ACU).
Possible values for this setting are:
Disabled
RX Enabled
TX Enabled
Auto-neegotiation (only available in some adapters)