Re: IFCAP_LRO on FreeBSD 7


On Thu, 27 Nov 2008, Yony Yossef wrote:

Is there a native interface for LRO in FreeBSD 7? I can't find any use for IFCAP_LRO but notifying the driver if to use or not to use this offload.

If not, is it planned for FreeBSD 8?

IFCAP_LRO is a capability/policy flag allowing drivers to declare support for LRO, and for administrators to enable/disable it if present. Drivers can either provide their own implementation (mxge, nxge) or use the system implementation (cxgb, igb). I'm slightly surprised to see that igb references tcp_lro_init() but not IFCAP_LRO -- perhaps lro isn't yet fully hooked up, or perhaps there's a bug? I believe all of the above applies to 7.1 but not 7.0, except possibly mxge supporting LRO in 7.0.

Robert N M Watson
Computer Laboratory
University of Cambridge
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