From owner-freebsd-net  Tue Oct 15 12:18:30 2002
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Date: Tue, 15 Oct 2002 12:16:31 -0700 (PDT)
From: Paul Herman <pherman@frenchfries.net>
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To: Steve Francis <steve@expertcity.com>
Cc: Kirill Ponomarew <ponomarew@oberon.net>,
	<freebsd-net@FreeBSD.ORG>
Subject: Re: delayed ACK
In-Reply-To: <3DAAE60E.3010708@expertcity.com>
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On Mon, 14 Oct 2002, Steve Francis wrote:

> Kirill Ponomarew wrote:
> >
> > is it recommended to use net.inet.tcp.delayed_ack=0 on the machines with
> > heavy network traffic ?
> >
> If you want to increase your network traffic for no particular reason,
> and increase load on your server, then yes.
>
> Otherwise no.

Not true.  Although some bugs have been fixed in 4.3, FreeBSD's
delayed ACKs will still degrade your performance dramatically in
some cases.

For now, the best advice I could give is to benchmark your client
machine with and without delayed ACKs and see which works best for
your environment.

-Paul.


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