From mboxrd@z Thu Jan 1 00:00:00 1970 From: "David Mosberger-Tang" Date: Wed, 12 Jul 2006 02:02:37 +0000 Subject: Re: [PATCH] ia64: change usermode HZ to 250 Message-Id: List-Id: References: <617E1C2C70743745A92448908E030B2A27FC5F@scsmsx411.amr.corp.intel.com> <1151578928.23785.0.camel@localhost.localdomain> <44A3AFFB.2000203@sgi.com> <1151578513.3122.22.camel@laptopd505.fenrus.org> <20060708001427.GA723842@sgi.com> <1152340963.3120.0.camel@laptopd505.fenrus.org> <20060710202228.GA732959@sgi.com> <20060711183754.GB734242@sgi.com> In-Reply-To: <20060711183754.GB734242@sgi.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Jeremy Higdon Cc: Arjan van de Ven , Jes Sorensen , Alan Cox , "Luck, Tony" , John Daiker , John Hawkes , Tony Luck , Andrew Morton , linux-ia64@vger.kernel.org, linux-kernel@vger.kernel.org, Jack Steiner , Dan Higgins On 7/11/06, Jeremy Higdon wrote: > Okay. So what do you think about changing the value in param.h from > 1024, so that it matches the new common value of 250, or is it best > just to leave it at 1024 and let applications that use it get the wrong > result? In my opinion, HZ needs to be a constant, since otherwise you could break perfectly fine existing code (e.g., code which statically initializes a variable with HZ and then picks up the correct frequency from sysconf) and if you have to pick a particular constant, it seems reasonable to me to pick the most commonly used frequency (which appears to be 250Hz at the moment). --david -- Mosberger Consulting LLC, http://www.mosberger-consulting.com/