From owner-freebsd-hackers Fri Jul 19 06:42:12 1996 Return-Path: owner-hackers Received: (from root@localhost) by freefall.freebsd.org (8.7.5/8.7.3) id GAA26386 for hackers-outgoing; Fri, 19 Jul 1996 06:42:12 -0700 (PDT) Received: from ns.ge.com (ns.ge.com [192.35.39.24]) by freefall.freebsd.org (8.7.5/8.7.3) with ESMTP id GAA26381 for ; Fri, 19 Jul 1996 06:42:07 -0700 (PDT) Received: from thomas.ge.com (thomas.ge.com [3.47.28.21]) by ns.ge.com (8.7.5/8.7.3) with ESMTP id JAA15182; Fri, 19 Jul 1996 09:39:29 -0400 Received: from salem.ge.com (carsdb.salem.ge.com [3.29.7.15]) by thomas.ge.com (8.7.5/8.6.12) with SMTP id IAA21552; Fri, 19 Jul 1996 08:26:58 -0400 Received: from combs.salem.ge.com by salem.ge.com (4.1/SMI-4.1) id AA21797; Fri, 19 Jul 96 09:39:14 EDT Received: from localhost (steve@localhost) by combs.salem.ge.com (8.7.5/8.6.11) with SMTP id JAA09872; Fri, 19 Jul 1996 09:39:14 -0400 (EDT) Date: Fri, 19 Jul 1996 09:39:14 -0400 (EDT) From: "Stephen F. Combs" Reply-To: CombsSF@salem.ge.com To: Amancio Hasty Cc: davidg@Root.COM, Heo Sung Gwan , freebsd-hackers@FreeBSD.org Subject: Re: your mail In-Reply-To: <199607191258.FAA00407@rah.star-gate.com> Message-Id: Mime-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-hackers@FreeBSD.org X-Loop: FreeBSD.org Precedence: bulk I didn't notice the original post, but Sybase uses RAW disk i/o as the preferred method for accessing database files (the files are just raw disk partitions, owned by the 'sybase' user). The 'sybase' user is a normal user, no special priv. This is under both SunO/S and HP-UX, don't know about other unixes. Under Windows N/T it just uses regular files (NT doesn't know about raw partitions!). ---- Stephen F. Combs Internet: CombsSF@Salem.GE.COM GE Industrial Systems Voice: 540.387.8828 Network Services Home: CombsSF-Home@Salem.GE.COM 1501 Roanoke Blvd FAX: 540.387.7106 Salem, VA 24153 LapTop: CombsSF-Mobile@Salem.GE.COM On Fri, 19 Jul 1996, Amancio Hasty wrote: > Date: Fri, 19 Jul 1996 05:58:14 -0700 > From: Amancio Hasty > To: davidg@Root.COM > Cc: Heo Sung Gwan , freebsd-hackers@FreeBSD.org > > >From The Desk Of David Greenman : > > > 4) How can user process access the file in ufs filesystem through raw disk? > > > > You can't unless you write a user-mode UFS/FFS that does it's I/O through > > the raw device. I couldn't imagine why you'd want to do this, however. > > > > My guess is that his assumption is that accessing the files via a > "raw disk mode" will be faster than going thru the normal file > access mechanism. I wish I knew what is he up to so we can help him or > better yet his justification for taking such approach . > > Amancio > > > >