From owner-freebsd-questions@FreeBSD.ORG Sat Jun 18 20:34:45 2005 Return-Path: X-Original-To: freebsd-questions@freebsd.org Delivered-To: freebsd-questions@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id AC80916A41C for ; Sat, 18 Jun 2005 20:34:45 +0000 (GMT) (envelope-from keramida@ceid.upatras.gr) Received: from nic.ach.sch.gr (nic.sch.gr [194.63.238.4]) by mx1.FreeBSD.org (Postfix) with ESMTP id EDC5C43D1F for ; Sat, 18 Jun 2005 20:34:44 +0000 (GMT) (envelope-from keramida@ceid.upatras.gr) Received: (qmail 17141 invoked by uid 207); 18 Jun 2005 20:34:44 -0000 Received: from keramida@ceid.upatras.gr by nic by uid 201 with qmail-scanner-1.21 (sophie: 3.04/2.19/3.81. Clear:RC:1(81.186.70.207):. Processed in 0.566984 secs); 18 Jun 2005 20:34:44 -0000 Received: from dialup207.ach.sch.gr (HELO gothmog.gr) ([81.186.70.207]) (envelope-sender ) by nic.sch.gr (qmail-ldap-1.03) with DES-CBC3-SHA encrypted SMTP for ; 18 Jun 2005 20:34:43 -0000 Received: from gothmog.gr (gothmog [127.0.0.1]) by gothmog.gr (8.13.4/8.13.4) with ESMTP id j5IKYd45002029; Sat, 18 Jun 2005 23:34:39 +0300 (EEST) (envelope-from keramida@ceid.upatras.gr) Received: (from giorgos@localhost) by gothmog.gr (8.13.4/8.13.4/Submit) id j5IKYc5F002027; Sat, 18 Jun 2005 23:34:38 +0300 (EEST) (envelope-from keramida@ceid.upatras.gr) Date: Sat, 18 Jun 2005 23:34:37 +0300 From: Giorgos Keramidas To: lefty@asda.gr Message-ID: <20050618203437.GA1966@gothmog.gr> References: <42B481D0.EFA31599@ene.asda.gr> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <42B481D0.EFA31599@ene.asda.gr> Cc: freebsd-questions@freebsd.org Subject: Re: Can't mount partitions with soft-updates enabled with async option X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 18 Jun 2005 20:34:45 -0000 On 2005-06-18 23:19, Lefteris Tsintjelis wrote: > I am not sure if I do something wrong here or it is suppose to work that > way but the async option doesn't seem to work for partitions that have > soft-updates turned on. Why would you want to do that? Soft-updates already provides most of the benefits of an async mount plus some extra goodies, like never leaving the filesystem in an inconsistent state. > Can someone please clarify the difference and if the speed difference > (if any) is significant when using the async option instead of the > soft-updates for cases such as the /usr/obj or as a squid data > storage? Is async preferred over soft-updates when data loss is not a > big issue? A speed comparison can be found in "The Design and Implementation of the FreeBSD Operating System". If I'm reading the relevant text correctly, then filesystems softupdates are slightly slower than async mounted filesystems and a hell of a lot faster than synchronous mounts without softupdates. The speed gain of mounting a squid cache as async shouldn't really be that big, but the guarantees of avoiding data loss when a filesystem is mounted with softupdates are too big to ignore :-)