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Date: Tue, 18 Dec 2007 10:10:23 -0800
From: David G Lawrence <dg@dglawrence.com>
To: Bruce Evans <brde@optusnet.com.au>
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Cc: freebsd-net@FreeBSD.org, freebsd-stable@FreeBSD.org
Subject: Re: Packet loss every 30.999 seconds
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> > I got an almost identical delay (with 64000 vnodes).
> > 
> > Now, 17ms isn't much.
> 
>    Says you. On modern systems, trying to run a pseudo real-time application
> on an otherwise quiescent system, 17ms is just short of an eternity. I agree
> that the syncer should be preemptable (which is what my bandaid patch
> attempts to do), but that probably wouldn't have helped my specific problem
> since my application was a user process, not a kernel thread.

   One more followup (I swear I'm done, really!)... I have a laptop here
that runs at 150MHz when it is in the lowest running CPU power save mode.
At that speed, this bug causes a delay of more than 300ms and is enough
to cause loss of keyboard input. I have to switch into high speed mode
before I try to type anything, else I end up with random typos. Very
annoying.

-DG

David G. Lawrence
President
Download Technologies, Inc. - http://www.downloadtech.com - (866) 399 8500
The FreeBSD Project - http://www.freebsd.org
Pave the road of life with opportunities.