User Manual

Rev 2.2-1.0.1
Mellanox Technologies
133
The following are the ethtool supported options:
Table 8 - ethtool Supported Options
Options Description
ethtool -i eth<x> Checks driver and device information.
For example:
#> ethtool -i eth2
driver: mlx4_en (MT_0DD0120009_CX3)
version: 2.1.6 (Aug 2013)
firmware-version: 2.30.3000
bus-info: 0000:1a:00.0
ethtool -k eth<x> Queries the stateless offload status.
ethtool -K eth<x> [rx on|off] [tx
on|off] [sg on|off] [tso on|off] [lro
on|off] [gro on|off] [gso on|off]
Sets the stateless offload status.
TCP Segmentation Offload (TSO), Generic Segmentation
Offload (GSO): increase outbound throughput by reducing
CPU overhead. It works by queuing up large buffers and
letting the network interface card split them into separate
packets.
Large Receive Offload (LRO): increases inbound through-
put of high-bandwidth network connections by reducing
CPU overhead. It works by aggregating multiple incoming
packets from a single stream into a larger buffer before
they are passed higher up the networking stack, thus
reducing the number of packets that have to be processed.
LRO is available in kernel versions < 3.1 for untagged
traffic.
Note: LRO will be done whenever possible. Otherwise
GRO will be done. Generic Receive Offload (GRO) is
available throughout all kernels.
ethtool -c eth<x> Queries interrupt coalescing settings.
ethtool -C eth<x> adaptive-rx
on|off
Enables/disables adaptive interrupt moderation.
By default, the driver uses adaptive interrupt moderation
for the receive path, which adjusts the moderation time to
the traffic pattern.
ethtool -C eth<x> [pkt-rate-low N]
[pkt-rate-high N] [rx-usecs-low N]
[rx-usecs-high N]
Sets the values for packet rate limits and for moderation
time high and low values.
• Above an upper limit of packet rate, adaptive moderation
will set the moderation time to its highest value.
• Below a lower limit of packet rate, the moderation time
will be set to its lowest value.