Configuring hardware offload operations
Some CPU-intensive operations can be offloaded to the OSA adapter, thus reducing the load on the host CPU.
The qeth device driver supports offloading for the following operations
on both layer 2 and layer 3:
- Inbound (receive) and outbound (transmit) checksum calculations for TCP and UDP network packets
- TCP segmentation
VLAN interfaces inherit offload settings from their base interface.
You can set the offload operations with the Linux®
ethtool command. See the ethtool man page for
details. The following abbreviated example shows some offload settings:
# ethtool -k eth0 Features for eth0: rx-checksumming: on tx-checksumming: on tx-checksum-ipv4: on tx-checksum-ip-generic: off [fixed] tx-checksum-ipv6: on tx-checksum-fcoe-crc: off [fixed] tx-checksum-sctp: off [fixed] scatter-gather: on tx-scatter-gather: on tx-scatter-gather-fraglist: off [fixed] tcp-segmentation-offload: on tx-tcp-segmentation: on tx-tcp-ecn-segmentation: off [fixed] tx-tcp6-segmentation: on udp-fragmentation-offload: off [fixed] generic-segmentation-offload: off [requested on] generic-receive-offload: on large-receive-offload: off [fixed] ...