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Date: Wed, 28 Aug 2002 07:25:01 -0700
To: yodaiken@fsmlabs.com, "Richard B. Johnson" <root@chaos.analogic.com>
From: Jonathan Lundell <linux@lundell-bros.com>
Subject: Re: interrupt latency
Cc: yodaiken@fsmlabs.com, Mark Hounschell <markh@compro.net>,
       "Wessler, Siegfried" <Siegfried.Wessler@de.hbm.com>,
       "'linux-kernel@vger.kernel.org'" <linux-kernel@vger.kernel.org>
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At 7:41 am -0600 8/28/02, yodaiken@fsmlabs.com wrote:
>Average and worst case are different.

I can believe that. The explanation that jumps to mind is PCI bus 
contention because of DMA, causing the inb to stall or to get 
repeatedly retried. 13us seems a little extreme, but not completely 
impossible.
-- 
/Jonathan Lundell.
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