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Date: Tue, 19 Oct 2004 06:16:25 -0400 (EDT)
From: Robert Watson <rwatson@FreeBSD.org>
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To: Scott Long <scottl@FreeBSD.org>
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Subject: Re: cvs commit: src/sys/dev/em if_em.c
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Nice catch.  I suspect we have a few more things like this floating
around...

Robert N M Watson             FreeBSD Core Team, TrustedBSD Projects
robert@fledge.watson.org      Principal Research Scientist, McAfee Research

On Tue, 19 Oct 2004, Scott Long wrote:

> scottl      2004-10-19 02:39:27 UTC
> 
>   FreeBSD src repository
> 
>   Modified files:
>     sys/dev/em           if_em.c 
>   Log:
>   Use an alignment of 1 instead of PAGE_SIZE for the rx and tx buffer tags.
>   Since the e1000 DMA engines hava no constraints on the alignment of buffer
>   transfers, there is no reason to tell busdma that there is.  This save a
>   minimum of 1 malloc call per packet, which translates to eliminating 4 locks.
>   It also means that buffers are not needlessly bounced when transfered.  The
>   end result is a 38% improvement in pps in a 4 way bridging environment.
>   
>   Obtained from: Sandvine, Inc.
>   
>   Revision  Changes    Path
>   1.48      +2 -12     src/sys/dev/em/if_em.c
>