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To: pyunyh@gmail.com
From: Ian FREISLICH <ianf@clue.co.za>
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Date: Thu, 11 Mar 2010 09:06:04 +0200
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Cc: David Christensen <davidch@broadcom.com>,
	"current@freebsd.org" <current@freebsd.org>
Subject: Re: dev.bce.X.com_no_buffers increasing and packet loss 
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Pyun YongHyeon wrote:
> On Wed, Mar 10, 2010 at 02:45:47PM -0800, David Christensen wrote:
> > The bce(4) hardware supports a linked list of pages for RX 
> > buffer descriptors.  The stock build supports 2 pages (RX_PAGES)
> > with a total of 511 BD's per page.  The hardware can support a
> > maximum of 64K BD's but that would be an unnecessarily large
> > amount of mbufs for an infrequent problem.

I think that depends on how you define infrequent.  Our use case
is a largish core router.  It's highly likely that we'll see this
again and again in various packet storms on our network.

Ian

--
Ian Freislich