From owner-freebsd-hackers Wed Mar 22 17:55:32 1995 Return-Path: hackers-owner Received: (from majordom@localhost) by freefall.cdrom.com (8.6.10/8.6.6) id RAA23069 for hackers-outgoing; Wed, 22 Mar 1995 17:55:32 -0800 Received: from Root.COM (implode.Root.COM [198.145.90.1]) by freefall.cdrom.com (8.6.10/8.6.6) with ESMTP id RAA23049 for ; Wed, 22 Mar 1995 17:55:28 -0800 Received: from jsdinc.root.com (uucp@localhost) by Root.COM (8.6.8/8.6.5) with UUCP id RAA04561; Wed, 22 Mar 1995 17:55:04 -0800 Received: (root@localhost) by jsdinc.root.com (8.6.11/8.6.5) id UAA00587; Wed, 22 Mar 1995 20:58:01 GMT From: "John S. Dyson" Message-Id: <199503222058.UAA00587@jsdinc.root.com> Subject: Re: Why IDE is bad To: cs.weber.edu!terry@implode.root.com (Terry Lambert) Date: Wed, 22 Mar 1995 20:58:00 +0000 () Cc: toor@Root.COM, star-gate.com!hasty@implode.root.com, hackers@FreeBSD.org In-Reply-To: <9503230134.AA15550@cs.weber.edu> from "Terry Lambert" at Mar 22, 95 06:34:54 pm X-Mailer: ELM [version 2.4 PL23] MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Content-Length: 1053 Sender: hackers-owner@FreeBSD.org Precedence: bulk > > What do you mean "async mounts"? > > Since kernel entry via system call is atomic unless you have SMP > or multithreading to support multiple kernel thread contexts, it > really can't be anything but synchronous. > > A UFS mount in the kernel goes to the device, reads the volume > header and superblock into core, gets a vnode for inode 2, and > arranges to have references to the vnode in the file system it > is mounted into return vnode 2 of the mounted fs. Then it > returns from the mount call. > > This is synchronous, but it is also guaranteed to be deterministically > quick, by definition. > > Am I missing something about what you mean when you say "async mounts"? > You are missing my point (listen to what I mean, not what I say :-)). What I meant was that the async option is essentially ignored. In essence, the UFS does not act differently whether or not the async option is specified. Hmm, true async mounts -- better hold up V2.1, sounds like a neat feature :-). (PLEASE DONT TAKE THIS SERIOUSLY). John dyson@root.com