From mboxrd@z Thu Jan  1 00:00:00 1970
From: Roland Dreier <rdreier@cisco.com>
Subject: Re: [RFC] New driver API to speed up small packets xmits
Date: Tue, 15 May 2007 14:08:23 -0700
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Cc: "David Miller" <davem@davemloft.net>, ak@suse.de,
	krkumar2@in.ibm.com, "netdev" <netdev@vger.kernel.org>
To: "Michael Chan" <mchan@broadcom.com>
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In-Reply-To: <1179265719.25622.40.camel@dell> (Michael Chan's message of "Tue, 15 May 2007 14:48:39 -0700")
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 > > Well, IPoIB doesn't do netif_wake_queue() until half the device's TX
 > > queue is free, so we should get batching.  However, I'm not sure that
 > > I can count on a fudge factor ensuring that there's enough space to
 > > handle everything skb_gso_segment() gives me -- is there any reliable
 > > way to get an upper bound on how many segments a given gso skb will
 > > use when it's segmented?
 > 
 > Take a look at tg3.c.  I use (gso_segs * 3) as the upper bound.

Thanks for the pointer... I noticed that code, but could you tell me
where the "* 3" comes from?

 - R.