From owner-freebsd-stable Tue Apr 14 08:49:10 1998 Return-Path: Received: (from majordom@localhost) by hub.freebsd.org (8.8.8/8.8.8) id IAA05865 for freebsd-stable-outgoing; Tue, 14 Apr 1998 08:49:10 -0700 (PDT) (envelope-from owner-freebsd-stable@FreeBSD.ORG) Received: from ns.frihet.com (root@frihet.bayarea.net [205.219.92.1]) by hub.freebsd.org (8.8.8/8.8.8) with ESMTP id PAA05814 for ; Tue, 14 Apr 1998 15:49:00 GMT (envelope-from tweten@ns.frihet.com) Received: from ns.frihet.com (tweten@localhost.frihet.com [127.0.0.1]) by ns.frihet.com (8.8.8/8.8.8) with ESMTP id IAA18006; Tue, 14 Apr 1998 08:48:29 -0700 (PDT) (envelope-from tweten@ns.frihet.com) Message-Id: <199804141548.IAA18006@ns.frihet.com> X-Mailer: exmh version 2.0.2 2/24/98 Reply-to: tweten@frihet.com To: chad@dcfinc.com Cc: pst@juniper.net, stable@FreeBSD.ORG Subject: Re: MFS in -stable? From: "David E. Tweten" Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Date: Tue, 14 Apr 1998 08:48:28 -0700 Sender: owner-freebsd-stable@FreeBSD.ORG Precedence: bulk Referring to MFS, chad@freebie.dcfinc.com said: >But if you left the memory available for Kernel buffers, wouldn't you >get the performance without the management headaches? You would get some of the benefit of MFS, if your temporary files were short-lived compared to the sync interval, if they didn't use up too many buffers, and if there weren't too much demand for real memory for processes. You'd still have to endure at least four synchronous disk writes per file for meta data, unless FreeBSD has implemented the recommendations of Ganger and Patt [USENIX SOSDI, 1994]. Their ideas on how to avoid synchronous meta data I/O without endangering file system integrity were definitely not part of 4.4BSD Lite. Synchronous writes to an MFS are _much_ faster than they are to a real disk. -- David E. Tweten | 2047-bit PGP fingerprint: | tweten@frihet.com 12141 Atrium Drive | E9 59 E7 5C 6B 88 B8 90 | tweten@and.com Saratoga, CA 95070-3162 | 65 30 2A A4 A0 BC 49 AE | (408) 446-4131 Those who make good products sell products; those who don't, sell solutions. To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-stable" in the body of the message