Dell Emulex Family of Adapters - Manual (Page 643)

Emulex Drivers for Windows User Manual P010077-01A Rev. A
3. Configuration
NIC Driver Configuration
643

An OCe14000-series adapter configures RoCE traffic for priority 5.

Manually enable priority 5 on the switch under a different priority
group other than FCoE/iSCSI/NIC priority group.
Note: If you do not enable priority 5 on the switch side, the OCe14000
adapter continues to be configured for PFC mode priority 5. This
configuration may result in packet losses, unrecoverable errors, or
infinite retries for RoCE traffic.

DCBX-disabled switch connection

When an OCe14000-series adapter is connected to DCBX-disabled switch, it
will be in generic pause mode.
Performance Considerations
The following recommended settings can improve SMB performance over TCP,
including RDMA. However, the configuration should be tuned to provide line rate
with TCP network traffic.
1. Disable TCP Autotuning
2. NIC MTU should be greater than RDMA MTU, which is recommended to be set at
4096. NIC MTU size of 9014 is recommended.
3. On Windows Server 2012 R2, disable the bandwidth throttling option on the SMB
client side to get good throughput. This parameter has no effect on Windows Server
2012:
Set-SmbClientConfiguration -EnableBandwidthThrottling 0
4. On a 40Gb link with a single client server configuration, increase the QP count to a
minimum of 8 for better throughput (please note that this will reduce the maximum
number shares that can be connected over RDMA):
Set-ItemProperty -Path
"HKLM:\SYSTEM\CurrentControlSet\Services\LanmanWorkstation\Parameters"
ConnectionCountPerRdmaNetworkInterface -Value 8 -Force
Configuring Multichannel
Note: RoCE is not supported when multichannel is enabled.
Multichannel, or UMC, allows you to divide a 10Gb port into multiple physical
functions with flexible bandwidth capacity allocation. These functions appear to the
operating system and network as separate physical devices.
Multichannel can be configured on OCe14000-series adapters through the adapter BIOS
or the OneCommand Manager application.

To configure multichannel using the adapter BIOS, see the Boot for NIC, iSCSI,
FCoE, and RoCE Protocols User Manual.

To configure multichannel using the OneCommand Manager application, see
the OneCommand Manager Application User Manual or the OneCommand Manager
Command Line Interface User Manual.