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Date: Wed, 21 Feb 2001 17:46:25 -0800
From: Rick Jones <raj@cup.hp.com>
Organization: the Unofficial HP
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To: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Nye Liu <nyet@curtis.curtisfong.org>, linux-kernel@vger.kernel.org
Subject: Re: Very high bandwith packet based interface and performance problems
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Alan Cox wrote:
> 
> > that because the kernel was getting 99% of the cpu, the application was
> > getting very little, and thus the read wasn't happening fast enough, and
> 
> Seems reasonable
> 
> > This is NOT what I'm seeing at all.. the kernel load appears to be
> > pegged at 100% (or very close to it), the user space app is getting
> > enough cpu time to read out about 10-20Mbit, and FURTHERMORE the kernel
> > appears to be ACKING ALL the traffic, which I don't understand at all
> > (e.g. the transmitter is simply blasting 300MBit of tcp unrestricted)
> 
> TCP _requires_ the remote end ack every 2nd frame regardless of progress.

um, I thought the spec says that ACK every 2nd segment is a SHOULD not a
MUST?

rick jones
-- 
ftp://ftp.cup.hp.com/dist/networking/misc/rachel/
these opinions are mine, all mine; HP might not want them anyway... :)
feel free to email, OR post, but please do NOT do BOTH...
my email address is raj in the cup.hp.com domain...
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