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From: Robert Watson <rwatson@FreeBSD.org>
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To: Yony Yossef <yonyossef.lists@gmail.com>
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Cc: jfv@FreeBSD.org, freebsd-hackers@freebsd.org, freebsd-net@freebsd.org
Subject: Re: IFCAP_LRO on FreeBSD 7
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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