From mboxrd@z Thu Jan  1 00:00:00 1970
From: Roland Dreier <rdreier@cisco.com>
Subject: Re: Dropping NETIF_F_SG since no checksum feature.
Date: Tue, 10 Oct 2006 20:33:46 -0700
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	<20061011002656.GB30093@mellanox.co.il>
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Cc: Stephen Hemminger <shemminger@osdl.org>,
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	Roland Dreier <rolandd@cisco.com>,
	"David S. Miller" <davem@davemloft.net>
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To: "Michael S. Tsirkin" <mst@mellanox.co.il>
In-Reply-To: <20061011002656.GB30093@mellanox.co.il> (Michael S. Tsirkin's message of "Wed, 11 Oct 2006 02:26:56 +0200")
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    Michael> My guess was, an extra pass over data is likely to be
    Michael> expensive - dirtying the cache if nothing else. But I do
    Michael> plan to measure that, and see.

I don't get it -- where's the extra pass?  If you can't compute the
checksum on the NIC then you have to compute sometime it on the CPU
before passing the data to the NIC.

 - R.