From owner-freebsd-net  Thu Oct 11 13:56:59 2001
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Date: Thu, 11 Oct 2001 16:50:42 -0400
To: Archie Cobbs <archie@dellroad.org>
From: Mike Tancsa <mike@sentex.net>
Subject: Re: strange results with increased
  net.inet.ip.intr_queue_maxlen
Cc: Luigi Rizzo <rizzo@aciri.org>, freebsd-net@FreeBSD.ORG
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At 01:38 PM 10/11/01 -0700, Archie Cobbs wrote:
>[ jumping into the middle of this discussion... ]
>
>Mike Tancsa writes:
> > net.inet.ip.intr_queue_maxlen from 50 to 100.  and there didnt seem to be
> > any positive results in terms of lessening the rate of
> > net.inet.ip.intr_queue_drops.
>
>This is consistent with the situation where packets are received
>at a rate faster than they are being consumed. No matter how big
>your queue is, it's going to fill up eventually and overflow, and
>all you're doing by increasing the queue length is adding latency
>to all of those packets that you do process.


Hi, thanks for the info.  But wont I still pay a price, presumably at the 
application layer for any packets that are lost and retransmitted ?  Apart 
from pinging the other side of the OC-3 or ethernet connection and 
measuring the response time, how can I see how much latency is added by 
increasing these buffers ?

         ---Mike


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