Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Tue, 8 Oct 2002 15:26:56 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Tue, 8 Oct 2002 15:26:03 -0400 Received: from packet.digeo.com ([12.110.80.53]:58087 "EHLO packet.digeo.com") by vger.kernel.org with ESMTP id ; Tue, 8 Oct 2002 15:24:49 -0400 Message-ID: <3DA33250.FB61BAAE@digeo.com> Date: Tue, 08 Oct 2002 12:30:24 -0700 From: Andrew Morton X-Mailer: Mozilla 4.79 [en] (X11; U; Linux 2.4.19-pre4 i686) X-Accept-Language: en MIME-Version: 1.0 To: Robert Love CC: Chris Wedgwood , linux-kernel@vger.kernel.org, riel@conectiva.com.br Subject: Re: [PATCH] O_STREAMING - flag for optimal streaming I/O References: <20021008190513.GA4728@tapu.f00f.org> <1034104637.29468.1483.camel@phantasy> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-OriginalArrivalTime: 08 Oct 2002 19:30:24.0410 (UTC) FILETIME=[261117A0:01C26F01] Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 876 Lines: 22 Robert Love wrote: > > ... > > Andrew, any experience on one vs. the other? I'd say that if you were designing a new application which streams large amount of data then yes, you would design it to use O_DIRECT. You would instantiate a separate IO worker thread and a message passing mechanism so that thread would pump your data for you, and would peform your readahead, etc. If your filesystem supports O_DIRECT, of course. Not all do. The strength of O_STREAMING is that you can take an existing, working, megahuge application and make it play better with the VM by changing a single line of code. No big redesign needed. - 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/