From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S964978AbWD0IdA (ORCPT ); Thu, 27 Apr 2006 04:33:00 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S964980AbWD0IdA (ORCPT ); Thu, 27 Apr 2006 04:33:00 -0400 Received: from pentafluge.infradead.org ([213.146.154.40]:21941 "EHLO pentafluge.infradead.org") by vger.kernel.org with ESMTP id S964978AbWD0Ic7 (ORCPT ); Thu, 27 Apr 2006 04:32:59 -0400 Subject: Re: A possibility of turning off file caching for certain operations From: Arjan van de Ven To: Artem Tashkinov Cc: linux-kernel@vger.kernel.org In-Reply-To: <20060427082922.77DB586B12@ws7-1.us4.outblaze.com> References: <20060427082922.77DB586B12@ws7-1.us4.outblaze.com> Content-Type: text/plain Date: Thu, 27 Apr 2006 10:32:56 +0200 Message-Id: <1146126777.2894.18.camel@laptopd505.fenrus.org> Mime-Version: 1.0 X-Mailer: Evolution 2.2.3 (2.2.3-2.fc4) Content-Transfer-Encoding: 7bit X-SRS-Rewrite: SMTP reverse-path rewritten from by pentafluge.infradead.org See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 2006-04-27 at 00:29 -0800, Artem Tashkinov wrote: > A nice feature of emptying files and buffer cache was introduced in kernel 2.6.16 but my question is: Is it possible to turn off file caching for certain operations? E.g. I do not want the kernel to cache an ISO image which is being copied from HDD to the LAN or burned to CD. it's called O_DIRECT and madvise() but do you rEALLY REALLY want to disable caching? Caching, even a little bit, is essential to get ok performance; if you disable caching it's your responsibility to do all the things needed to get good IO performance.