User`s guide

NIC Acceleration Features
007-5476-001 21
The following entry dumps the current settings:
cxgbtool intf qset
The following entry updates the holdoff timer value for queue X to Y usecs:
cxgbtool intf qset X lat Y
NIC Acceleration Features
The adapter supports all widespread acceleration features:
• Checksum offload
• TCP segmentation offload (TSO)
• Large receive offload (LRO)
Checksum offload and TSO are controlled through ethtool(8).
Currently, ethtool(8) is not well suited to deal with hardware that supports multiple
receive queues. The interface cxgbtool(8) provides the facility to control LRO on a
per-recieve-queue basis. The following entry dumps the current settings:
cxgbtool intf qset
The following entry disables/enables the LRO capability for queue X:
cxgbtool intf qset X lro [0|1]
Software (SW) Stack Tuning
The SW stack can be tuned to improve TCP performance as follows:
Set net.core.wmem_max=”16777216”
Set net.core.rmem_max=”16777216”
Set net.ipv4.tcp_timestamps=”0”
Set net.ipv4.tcp_rmem=”4096 262144 16777216”
Set net.ipv4.tcp_wmem=”4096 262144 16777216”
Set net.core.optmem_max=”524288”
Set net.core.netdev_max_backlog=”200000”