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From: naddy@mips.inka.de (Christian Weisgerber)
Date: Sat, 9 Aug 2008 20:12:42 +0000 (UTC)
Message-ID: <g7ktnq$glp$1@lorvorc.mips.inka.de>
Originator: naddy@mips.inka.de (Christian Weisgerber)
To: freebsd-net@freebsd.org
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Subject: Rx/tx hardware checksumming statistics?
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OpenBSD keeps count of the packets that have undergone IPv4 header/
TCP/UDP checksumming in hardware.  These statics are available with
netstat -s, e.g.:

ip:
    ...
        492152 input datagrams checksum-processed by hardware
        911338 output datagrams checksum-processed by hardware
    ...

This comes in quite handy to check whether checksum offloading
actually works and which protocols are successfully processed this
way.

On FreeBSD, netstat -s does not provide this information.  Are these
statistics available in some other way?  How would I check whether
packets have actually been checksummed in hardware?

-- 
Christian "naddy" Weisgerber                          naddy@mips.inka.de