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From: "David S. Miller" <davem@redhat.com>
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Date: Fri, 2 Feb 2001 15:31:41 -0800 (PST)
To: David Lang <dlang@diginsite.com>
Cc: Andrew Morton <andrewm@uow.edu.au>, lkml <linux-kernel@vger.kernel.org>,
        "netdev@oss.sgi.com" <netdev@oss.sgi.com>
Subject: Re: sendfile+zerocopy: fairly sexy (nothing to do with ECN)
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David Lang writes:
 > right, assuming that there is enough sendfile() benifit to overcome the
 > write() penalty from the stuff that can't be cached or sent from a file.
 > 
 > my question was basicly are there enough places where sendfile would
 > actually be used to make it a net gain.

There are non-performance issues as well (really, all of these points
have been mentioned in this thread btw).  One is that since paged
SKBs use only single-order page allocations, the memory allocation
subsystem is stressed less than the current scheme where SLAB
allocates multi-order pages to satisfy allocations of linear SKB data
buffers.

This has consequences and benefits system wide.

Later,
David S. Miller
davem@redhat.com
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