From owner-freebsd-stable@FreeBSD.ORG Fri Apr 1 15:42:34 2011 Return-Path: Delivered-To: freebsd-stable@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id EC7781065672 for ; Fri, 1 Apr 2011 15:42:33 +0000 (UTC) (envelope-from amarat@ksu.ru) Received: from mx3.ksu.ru (mx3.ksu.ru [83.69.96.40]) by mx1.freebsd.org (Postfix) with ESMTP id ED4BE8FC15 for ; Fri, 1 Apr 2011 15:42:32 +0000 (UTC) Received: from unknown (HELO ruby.ksu.ru) ([178.213.240.4]) by ironport1.ksu.ru with ESMTP; 01 Apr 2011 19:42:18 +0400 X-Pass-Through: Kazan State University Network Received: from zealot.ksu.ru ([194.85.245.161]) by ksu.ru (8.13.4/8.13.4) with ESMTP id p31FXHhs013323; Fri, 1 Apr 2011 15:33:17 GMT Received: from zealot.ksu.ru (localhost.lnet [127.0.0.1]) by zealot.ksu.ru (8.14.4/8.14.4) with ESMTP id p31Fbejl038274; Fri, 1 Apr 2011 19:37:40 +0400 (MSD) (envelope-from amarat@ksu.ru) Message-ID: <4D95F143.8080001@ksu.ru> Date: Fri, 01 Apr 2011 19:37:39 +0400 From: "Marat N.Afanasyev" User-Agent: Mozilla/5.0 (X11; U; FreeBSD amd64; en-US; rv:1.9.1.16) Gecko/20101215 Firefox/3.6.15 MIME-Version: 1.0 To: Marko Lerota References: <87d3l6p5xv.fsf@cosmos.claresco.hr> <874o6ip0ak.fsf@cosmos.claresco.hr> In-Reply-To: <874o6ip0ak.fsf@cosmos.claresco.hr> Content-Type: multipart/signed; protocol="application/pkcs7-signature"; micalg=sha1; boundary="------------ms080903030903020306070002" X-Content-Filtered-By: Mailman/MimeDel 2.1.5 Cc: freebsd-stable@freebsd.org Subject: Re: Constant rebooting after power loss X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 01 Apr 2011 15:42:34 -0000 This is a cryptographically signed message in MIME format. --------------ms080903030903020306070002 Content-Type: text/plain; charset=KOI8-R; format=flowed Content-Transfer-Encoding: quoted-printable Marko Lerota wrote: > George Kontostanos writes: > >> Not with the same behavior and it depends on what your server is doing= at >> the time of the power interruption. > > It was in stage of booting after first power loss. > >> but ZFS is not the solution to your problem. ZFS is not designed to re= place >> the needs of a UPS. > > I'm just asking if this wouldn't happen if I used ZFS. I read that ZFS > don't need fsck because the files are always consistent on filesystem > regardless of power loses. That the corruption can occur only if disks > are damaged. But not when power goes down. I'm not planing to buy UPS > for home use. > to ensure consistency you should turn off physical drive caches, and=20 degrade performance significantly, sometimes up to 1000x. if this is=20 what you want, you may use either zfs or sync ufs. in such case you may=20 be almost sure that your filesystems are consistent. but if you use=20 drive's cache, then without UPS you will face data loss and vanished=20 filesystem earlier or later --=20 =F3 =D5=D7=C1=D6=C5=CE=C9=C5=CD, =ED=C1=D2=C1=D4 =E1=C6=C1=CE=C1=D3=D8=C5= =D7 --------------ms080903030903020306070002--