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Date: Mon, 15 Mar 2004 08:17:13 +0000
From: Jamie Lokier <jamie@shareable.org>
To: Horst von Brand <vonbrand@inf.utfsm.cl>
Cc: lkml <linux-kernel@vger.kernel.org>
Subject: Re: finding out the value of HZ from userspace
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References: <20040311141703.GE3053@luna.mooo.com> <200403140245.i2E2jKSx005375@eeyore.valparaiso.cl>
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Horst von Brand wrote:
> What for? It should be invisible to userspace...

It's not invisible.  select/poll/epoll/setitimer round their time
argument according to HZ, and programs which do smooth (i.e. low
_jitter_) animation of the kind where the eye is sensitive to the
jitter need to track it and correct for it.

-- Jamie