Chelsio Communications Chelsio T4 Betriebsanweisung PDF herunterladen (Seite 49)

Chapter II. Network (NIC/TOE)



If you would like to use the Linux GRO/LRO for any reason, first the t4_tom kernel module

needs to be removed from kernel module list. Please note you might need to reboot your

system.

After removing the t4_tom module, you can use ethtool to check the status of current

GRO/LRO settings, for example:

[root@host]# ethtool -k eth6

Offload parameters for eth6:

rx-checksumming: on

tx-checksumming: on

scatter-gather: on

tcp-segmentation-offload: on

udp-fragmentation-offload: off

generic-segmentation-offload: on

generic-receive-offload: on

large-receive-offload: off

Now the generic-receive-offload option is on. This means GRO is enabled. Please note

that there are two offload options here: generic-receive-offload and large-receive-

offload. This is because on this Linux system (RHEL6.0), the kernel supports both GRO and

LRO. As mentioned earlier, GRO is always the preferred option when both of them are present.

On other systems LRO might be the only available option. Then ethtool could be used to

switch LRO on and off as well.

-related statistics. They

are displayed using the following command:

[root@host]# ethtool -S eth6

...

GROPackets : 0

GROMerged : 897723

...

GROPackets is the number of held packets. Those are candidate packets held by the kernel to

be processed individually or to be merged to larger packets. This number is usually zero.

GROMerged is the number of packets that merged to larger packets. Usually this number

increases if there is any continuous traffic stream present.

1 2 ... 44 45 46 47 48 49 50 51 52 53 54 ... 373 374

Keine Kommentare

Chelsio Communications Chelsio T4 Betriebsanweisung Seite 49