Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261400AbVETJWK (ORCPT ); Fri, 20 May 2005 05:22:10 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261395AbVETJWK (ORCPT ); Fri, 20 May 2005 05:22:10 -0400 Received: from hermine.aitel.hist.no ([158.38.50.15]:61195 "HELO hermine.aitel.hist.no") by vger.kernel.org with SMTP id S261400AbVETJV6 (ORCPT ); Fri, 20 May 2005 05:21:58 -0400 Message-ID: <428DAD71.4050105@aitel.hist.no> Date: Fri, 20 May 2005 11:27:13 +0200 From: Helge Hafting User-Agent: Debian Thunderbird 1.0.2 (X11/20050331) X-Accept-Language: en-us, en MIME-Version: 1.0 To: Ben Greear CC: Arjan van de Ven , linux-os@analogic.com, Adrian Bunk , Kyle Moffett , "Gilbert, John" , linux-kernel@vger.kernel.org Subject: Re: Illegal use of reserved word in system.h References: <2692A548B75777458914AC89297DD7DA08B0866F@bronze.dolby.net> <20050518195337.GX5112@stusta.de> <6EA08D88-7C67-48ED-A9EF-FEAAB92D8B8F@mac.com> <20050519112840.GE5112@stusta.de> <1116505655.6027.45.camel@laptopd505.fenrus.org> <428CCD19.6030909@candelatech.com> In-Reply-To: <428CCD19.6030909@candelatech.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1072 Lines: 28 Ben Greear wrote: > Arjan van de Ven wrote: > >> HZ may not exist. At all; people are trying to remove it. And userspace >> has no business knowing about it either. > > > It can be helpful to know what HZ you are running at, for instance if > you care > very much about the (average) precision of a select/poll timeout. > Will knowing it help? You may find out that you don't have much precision, but then theres nothing to do about it. And there may not even be a HZ, as mentioned. Less cpu is used if there is no periodic interrupts when there is nothing to do. People are trying to *not* have a regular timer interrupt; instead, a one-shot timer can be programmed for the next necessary timeout which may very well be quite a few "ticks" into the future. In this case there is no notion of HZ at all. Helge Hafting - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/