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declance questions

To: linux-mips@fnet.fr
Subject: declance questions
From: Florian Lohoff <flo@rfc822.org>
Date: Sat, 2 Jan 1999 00:20:52 +0100
Sender: flo@mini.gt.owl.de
Hi,
i found out that the transfers of the declance/nfs are VERY bursty.
If you look at an tcpdump you see that you have heavy activity some
seconds (10-30) and then a delay of couple of seconds to minutes.

Also - is it correct that data from&to the ethernet is copied 
via CPU ?

--------------schnipp-----------------
        /*
         * copy 16 Byte chunks
         */
        clen = len >> 4;
        tp = (unsigned short *)to;
        fp = (unsigned short *)from;
        while (clen--) {
                *tp++ = *fp++;
                *tp++ = *fp++;
                *tp++ = *fp++;
                *tp++ = *fp++;
                *tp++ = *fp++;
                *tp++ = *fp++;
                *tp++ = *fp++;
                *tp++ = *fp++;
                tp += 8;
        }
--------------schnapp-----------------

The comment says that there is an misalignment for the skbs ?
But i remember reading in one of the TC DMA Docs TcIA or something
about byte alignment.

Flo
-- 
Florian Lohoff          flo@rfc822.org                  +49-5241-470566
Good, Fast, Cheap: Pick any two (you can't have all three).  (RFC 1925)

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