Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Fri, 26 Oct 2001 13:52:20 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Fri, 26 Oct 2001 13:52:10 -0400 Received: from lightning.swansea.linux.org.uk ([194.168.151.1]:30220 "EHLO the-village.bc.nu") by vger.kernel.org with ESMTP id ; Fri, 26 Oct 2001 13:51:58 -0400 Subject: Re: Linux 2.4.13-ac1 To: andrea@suse.de (Andrea Arcangeli) Date: Fri, 26 Oct 2001 18:54:00 +0100 (BST) Cc: alan@lxorguk.ukuu.org.uk (Alan Cox), cswingle@iarc.uaf.edu (Christopher S. Swingley), linux-kernel@vger.kernel.org In-Reply-To: <20011026194301.M30905@athlon.random> from "Andrea Arcangeli" at Oct 26, 2001 07:43:01 PM X-Mailer: ELM [version 2.5 PL6] MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Message-Id: From: Alan Cox Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org > simply because the <2.4.10 buffer cache layer wasn't able to do proper > readahead on the blkdev. Now we do readahead properly and so in turn > the the lack of media-change trust of the vfs shows up. So as far I can > tell the right fix have no influence on the blkdev in pagecache, but it > only consists in resurrecting the media-change detection with a > per-device bitflag whitelist. I cannot see other source of stalls across > a close/open cycle. I'm not currently sure if the impact is from the cost of the page cache flushing or the invalidate/re-read it triggers. There probably are two or three seeks on the DVD if the data is invalidated so that would make sense. Alan - 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/