From owner-freebsd-stable@FreeBSD.ORG Wed Feb 15 06:27:21 2012 Return-Path: Delivered-To: freebsd-stable@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id E2484106564A for ; Wed, 15 Feb 2012 06:27:20 +0000 (UTC) (envelope-from amvandemore@gmail.com) Received: from mail-ww0-f42.google.com (mail-ww0-f42.google.com [74.125.82.42]) by mx1.freebsd.org (Postfix) with ESMTP id 6C3A98FC0C for ; Wed, 15 Feb 2012 06:27:20 +0000 (UTC) Received: by wgbgn7 with SMTP id gn7so3862993wgb.1 for ; Tue, 14 Feb 2012 22:27:19 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type; bh=xlaz9rT9RtG/b9KzW3Ch2IhEBSE76nSgsqnumWByBkM=; b=cb0b264s6GAlqglQP2pz6tXzWxw9RZqV2uZ+GFNsE/7aEIVAfr0DbHQ+xb2uRdqyGT 9Pz6YiLpWJpxjR6zrF6S6f2bSQzka2PDzAdZqPRP54VKty4mINAr0siQ0kfVoH+aYZ5f cdQIU81f8TAwtR86BKWIVTmTrMPfpsbufoW14= MIME-Version: 1.0 Received: by 10.180.24.166 with SMTP id v6mr6451191wif.10.1329287239337; Tue, 14 Feb 2012 22:27:19 -0800 (PST) Received: by 10.223.62.70 with HTTP; Tue, 14 Feb 2012 22:27:19 -0800 (PST) In-Reply-To: References: <4F215A99.8020003@os2.kiev.ua> <4F27C04F.7020400@omnilan.de> <4F27C7C7.3060807@os2.kiev.ua> <4F37F81E.7070100@os2.kiev.ua> <4F38AF69.6010506@os2.kiev.ua> <20120213132821.GA78733@in-addr.com> <20120214200258.GA29641@server.vk2pj.dyndns.org> Date: Wed, 15 Feb 2012 00:27:19 -0600 Message-ID: From: Adam Vande More To: Scott Long Content-Type: text/plain; charset=ISO-8859-1 X-Content-Filtered-By: Mailman/MimeDel 2.1.5 Cc: freebsd-stable@freebsd.org, Peter Jeremy Subject: Re: disk devices speed is ugly X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 15 Feb 2012 06:27:21 -0000 On Tue, Feb 14, 2012 at 10:50 PM, Scott Long wrote: > > Any filesystem that uses bread/bwrite/cluster_read are already using the > "generic caching subsystem" that you propose. This includes UDF, CD9660, > MSDOS, NTFS, XFS, ReiserFS, EXT2FS, and HPFS, i.e. every local storage > filesystem in the tree except for ZFS. Not all of them implement > VOP_GETPAGES/VOP_PUTPAGES, but those are just optimizations for the vnode > pager, not requirements for using buffer-cache services on block devices. > As Kostik pointed out in a parallel email, the only thing that was removed > from FreeBSD was the userland interface to cached devices via /dev nodes. > Does this mean the Architecture Handbook page is wrong?: http://www.freebsd.org/doc/en/books/arch-handbook/driverbasics-block.html -- Adam Vande More