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Date: Mon, 20 Oct 2008 10:39:38 -0700
From: Alfred Perlstein <alfred@freebsd.org>
To: Len Gross <sandiegobiker@gmail.com>
Message-ID: <20081020173938.GL22503@elvis.mu.org>
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Cc: "freebsd-net@freebsd.org" <freebsd-net@freebsd.org>
Subject: Re: Timers in drivers vs userland
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Have you tried using rtprio?

You'll have to be really careful though so as not to jam up the
system using it.

-Alfred

* Len Gross <sandiegobiker@gmail.com> [081018 17:28] wrote:
> Slight correction; I should have said more accurate usleep, not "timer."
> 
> -- Len
> 
> On Sat, Oct 18, 2008 at 3:12 PM, Len Gross <sandiegobiker@gmail.com> wrote:
> > If I place a timer directly in a driver (like Ethernet)  will it be
> > subject to less jitter and more consistency than if it were in
> > Userland?
> >
> > I know FreeBSD is not "real time," but I need to be able to run a
> > polling algorithm with about 1 ms accuracy.
> >
> > Thanks in advance.
> >
> > (Please tell me if there is a better list for this question.)
> >
> > -- Len
> >
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-- 
- Alfred Perlstein