From owner-freebsd-net  Thu Oct 11 13:45: 7 2001
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From: Archie Cobbs <archie@dellroad.org>
Message-Id: <200110112038.f9BKclh17562@arch20m.dellroad.org>
Subject: Re: strange results with increased net.inet.ip.intr_queue_maxlen
In-Reply-To: <5.1.0.14.0.20011011121308.053ddc20@marble.sentex.ca>
 "from Mike Tancsa at Oct 11, 2001 12:19:01 pm"
To: Mike Tancsa <mike@sentex.net>
Date: Thu, 11 Oct 2001 13:38:47 -0700 (PDT)
Cc: Luigi Rizzo <rizzo@aciri.org>, freebsd-net@FreeBSD.ORG
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[ 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.

-Archie

__________________________________________________________________________
Archie Cobbs     *     Packet Design     *     http://www.packetdesign.com

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