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From: James Ausmus <james.ausmus@gmail.com>
To: gentoo-embedded@lists.gentoo.org
Subject: Re: [gentoo-embedded] SOLUTION (partial) was: High Speed Serial  Problem
Date: Mon, 22 Mar 2010 22:19:17 -0700	[thread overview]
Message-ID: <b79f23071003222219j1a8a4d8bi7a429e214a5f5fa2@mail.gmail.com> (raw)
In-Reply-To: <20100320150237.2ee70a4e@osage.osagesoftware.com>

On Sat, Mar 20, 2010 at 12:02 PM, David Relson <relson@osagesoftware.com> wrote:
<snip>
> Even with a dedicated thread, the program is still receiving multiple
> characters per read.  Calculating average and maximum byte counts for
> each 10,000 reads, I've often seen maximums of 150 and have never seen
> an average under 12.  These numbers occur with VMIN=1 and VTIME=0.
>
> Is there a setting so that the serial port driver will release
> characters sooner (rather than later)?
<snip>

Wasn't involved in the other thread, so my apologies if this has
already been answered/stated, but are you using the realtime kernel
patches? If you run RT-Preempt, then you can set the priority of the
kernel thread that is handling the serial interrupt high than all the
other kernel threads, which should improve your latencies... See
https://rt.wiki.kernel.org/index.php/Main_Page for more info.

HTH-

James


> Regards,
>
> David
>
>



  reply	other threads:[~2010-03-23  6:04 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2010-03-14 14:24 [gentoo-embedded] High Speed Serial Problem David Relson
2010-03-14 16:34 ` Manuel Lauss
2010-03-14 17:14   ` David Relson
2010-03-14 17:51 ` Peter Stuge
2010-03-15  1:47 ` Peter Bell
2010-03-15 13:34 ` Bob Dunlop
2010-03-15 17:47   ` Relson, David
2010-03-20 19:02     ` [gentoo-embedded] SOLUTION (partial) was: " David Relson
2010-03-23  5:19       ` James Ausmus [this message]
2010-03-15 14:07 ` [gentoo-embedded] " wireless

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