Subject: Re: [ANNOUNCE] Linux 2.6 Real Time Kernel
From: Robert Love <rml@novell.com>
To: Lee Revell <rlrevell@joe-job.com>
Cc: stefan.eletzhofer@eletztrick.de,
       linux-kernel <linux-kernel@vger.kernel.org>
In-Reply-To: <1097351221.1428.46.camel@krustophenia.net>
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	 <1097350227.1428.41.camel@krustophenia.net>
	 <20041009213817.GB25441@tier.local>
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Date: Sat, 09 Oct 2004 16:20:25 -0400
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On Sat, 2004-10-09 at 15:47 -0400, Lee Revell wrote:

> Yes.  The upper bound on the response time of an RT task is a function
> of the longest non-preemptible code path in the kernel.  Currently this
> is the processing of a single packet by netif_receive_skb.
> 
> AIUI hard realtime is about bounded response times.  How does this not
> qualify?

I am actually in agreement with you, favoring this soft real-time
approach, but this is not bounded response time or determinism.  There
are no guarantees, no measurements conducted with all possible inputs,
sizes, errors, and so on.  This soft real-time approach gives great
average case--but the worst case is only a measurement on a specific
machine in a specific workload.

	Robert Love


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