Intel 82574L NIC - Enable segmentation and large receive offload?



  • I'm using a Supermicro X7SPA-HF-O motherboard which has 2x Intel 82574L NICs.

    The documentation says it supports checksum offload and TCP segmentation offloading (TSO v2) but I don't see anything about large receive offload support (LRO).

    Should I enable these features in pfsense?  Is there any benefit (or harm?) for a home network?



  • I have been running 2 82574's on my pfSense box for a few years now, with all 3 hardware offloads ENABLED. Has been fine!



  • Try them, run a test? - really on a home network a reboot is not such a big deal.



  • Thanks for the info.

    I didn't want to try it without knowing because I read it could cause performance problems and I didn't want random or strange problems that might of been hard to track down.



  • Shouldn't these features only help when fragmenting or coalescing TCP data packets across different MTU boundaries? If this is the case, then the feature shouldn't help much for Internet related traffic as 1500mtu is extremely common.

    This is kind of a question and statement in one. I'm curious how wrong I may be.



  • The TCP checksum offload can actually be reasonably beneficial, especially at higher bandwidths.



  • @extide:

    The TCP checksum offload can actually be reasonably beneficial, especially at higher bandwidths.

    For endpoints, sure, but how would it help for a router, where traffic is just passing through?

    EDIT: I guess NAT would in the general case require the TCP checksum to be updated.



  • TCP Checksum is verified for every packet afaik