From owner-cvs-all Sun Nov 28 4:17:33 1999 Delivered-To: cvs-all@freebsd.org Received: from freja.webgiro.com (freja.webgiro.com [212.209.29.10]) by hub.freebsd.org (Postfix) with ESMTP id 326FD155EC; Sun, 28 Nov 1999 04:17:26 -0800 (PST) (envelope-from abial@webgiro.com) Received: by freja.webgiro.com (Postfix, from userid 1001) id 9748A1927; Sun, 28 Nov 1999 13:18:12 +0100 (CET) Received: from localhost (localhost [127.0.0.1]) by freja.webgiro.com (Postfix) with ESMTP id 3A9D149D2; Sun, 28 Nov 1999 13:18:12 +0100 (CET) Date: Sun, 28 Nov 1999 13:18:12 +0100 (CET) From: Andrzej Bialecki To: Poul-Henning Kamp Cc: cvs-committers@freebsd.org, cvs-all@freebsd.org Subject: Re: cvs commit: src/sys/conf options src/sys/dev/md md.c src/sys/i386/conf GENERIC LINT PCCARD src/sys/kern vfs_conf.c src/sys/sys conf.h src/sys/ufs/mfs mfs_vfsops.c In-Reply-To: <15595.943787689@critter.freebsd.dk> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-cvs-all@FreeBSD.ORG Precedence: bulk On Sun, 28 Nov 1999, Poul-Henning Kamp wrote: > In message , Andrze > j Bialecki writes: > > >I'm using MFS for many things. I feel a bit uneasy now, because of lack of > >information about the new md device. It seems to me that MFS got somehow > >"deprecated", but I'm not sure at all what the MD gives us instead... > > The root filesystem capability got moved from MFS to md because the > way MFS did it was rather nasty from an architecture point of view. > > >Could you shortly explain pros/cons of MD vs. MFS, difference in > >functionality (esp. lost functionality) > > There are no lost functionality. Wow, that's short! :-/ Anything else? Initializing from FS image? Using swap? How does it affect VM resources? Does it wire down the kernel memory? What is the overhead as compared to MFS? > > how the MD affects system > >resources? > > You need the md driver in your kernel. Hehe... See questions above. > > Are you going to remove MFS altogether from the -current? > > no. Ok. MD looks intriguing, but I (we?) need to know more how it affects the system, not just 'no loss of functionality' statement. Eg. let's suppose I have a machine with 512MB memory, and I want to use 256MB fo memory FS on /tmp. What difference will this have on VM resources in case of MD and MFS? Do they actually allocate all the pages, even unused? What happens to the free FS blocks?Do they take space? Does the MD device return unused pages to the system? etc, etc... Andrzej Bialecki // WebGiro AB, Sweden (http://www.webgiro.com) // ------------------------------------------------------------------- // ------ FreeBSD: The Power to Serve. http://www.freebsd.org -------- // --- Small & Embedded FreeBSD: http://www.freebsd.org/~picobsd/ ---- To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe cvs-all" in the body of the message