From mboxrd@z Thu Jan  1 00:00:00 1970
From: "David Mosberger-Tang" <David.Mosberger@acm.org>
Date: Tue, 11 Jul 2006 03:01:53 +0000
Subject: Re: [PATCH] ia64: change usermode HZ to 250
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To: Jeremy Higdon <jeremy@sgi.com>
Cc: Arjan van de Ven <arjan@infradead.org>, Jes Sorensen <jes@sgi.com>, Alan Cox <alan@lxorguk.ukuu.org.uk>, "Luck, Tony" <tony.luck@intel.com>, John Daiker <jdaiker@osdl.org>, John Hawkes <hawkes@sgi.com>, Tony Luck <tony.luck@gmail.com>, Andrew Morton <akpm@osdl.org>, linux-ia64@vger.kernel.org, linux-kernel@vger.kernel.org, Jack Steiner <steiner@sgi.com>, Dan Higgins <djh@sgi.com>

On 7/10/06, Jeremy Higdon <jeremy@sgi.com> wrote:
> On Sat, Jul 08, 2006 at 07:07:14AM -0600, David Mosberger-Tang wrote:
> > Nothing is broken.  Read Alan's statement carefully...
> >
> >  --david
>
> His statement can be read a couple of ways.

Alan said:

--------------------------------------------------------------
From: Alan Cox <alan_at_lxorguk.ukuu.org.uk>
Date: 2006-06-29 21:02:08

Ar Iau, 2006-06-29 am 05:37 -0400, ysgrifennodd Jes Sorensen:
> You have my vote for that one. Anything else is just going to cause
> those broken userapps to continue doing the wrong thing. We should
> really do this on all archs though.

No need, all current mainstream architectures expose a constant user HZ.

Alan
--------------------------------------------------------------

Note that Alan didn't claim that *all* (Linux-supported) architectures
expose a constant user HZ, only the "mainstream" ones.  I won't get
into the debate as to what qualifies as "mainstream", but clearly IA64
does not (and should not) expose a constant value, since there were no
legacy-binary-issue and we chose to insist that apps should uses
sysconf() or equivalent if they need to know the clocktick.

  --david
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