From owner-freebsd-questions@FreeBSD.ORG Sat Apr 19 17:20:30 2008 Return-Path: Delivered-To: freebsd-questions@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id C0A16106567F for ; Sat, 19 Apr 2008 17:20:30 +0000 (UTC) (envelope-from ivoras@gmail.com) Received: from rv-out-0506.google.com (rv-out-0506.google.com [209.85.198.229]) by mx1.freebsd.org (Postfix) with ESMTP id 8FD5B8FC57 for ; Sat, 19 Apr 2008 17:20:30 +0000 (UTC) (envelope-from ivoras@gmail.com) Received: by rv-out-0506.google.com with SMTP id b25so712600rvf.43 for ; Sat, 19 Apr 2008 10:20:30 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:received:received:message-id:date:from:sender:to:subject:cc:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references:x-google-sender-auth; bh=FcJE+rEPrFX4/lLrAZu3qATfuUUoqlCLMVDO1J6o2pI=; b=eK3PYMD5lt+bodi3DXiYSpI+b5PlZW8N7rNqIcVfphXskdQIKx1C9r2x7hw4FpSUmDJskAWNyF1U9Dm1eS22HXxS6NHI2ETmTou+1DPG/tYO4v+l1kGfzKF3JPg2Gyio+TXbnntVKsYJ1haWJiUh+qc76kCZjtO9ta+SF+1fboc= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=message-id:date:from:sender:to:subject:cc:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references:x-google-sender-auth; b=G4lmct/nqRsNobaTh26sH/qlcFdear6iveWX7XAHoQ/2Ih2UAQHAQoCwaiWpMYXVejk+KpmJk2TOvCRuQ1r3VzM0bjJwSdZoMZ8CtMt43Je6V4+rTrlZvFqI0lo02weep0i6H8VOnDmYUoMkOU905pix42v3xapzIRKmRxUxoWY= Received: by 10.140.188.10 with SMTP id l10mr2319109rvf.6.1208625630196; Sat, 19 Apr 2008 10:20:30 -0700 (PDT) Received: by 10.141.212.1 with HTTP; Sat, 19 Apr 2008 10:20:30 -0700 (PDT) Message-ID: <9bbcef730804191020v735614b6j26333a118c7d05b9@mail.gmail.com> Date: Sat, 19 Apr 2008 19:20:30 +0200 From: "Ivan Voras" Sender: ivoras@gmail.com To: Unga In-Reply-To: <293157.38247.qm@web57001.mail.re3.yahoo.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Content-Disposition: inline References: <9bbcef730804180840y77adff73x7ad0cf90c82633a9@mail.gmail.com> <293157.38247.qm@web57001.mail.re3.yahoo.com> X-Google-Sender-Auth: 944194256e18a44d Cc: freebsd-questions@freebsd.org Subject: Re: UFS2 Journaling implementation detail 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, 19 Apr 2008 17:20:30 -0000 2008/4/19 Unga : > --- Ivan Voras wrote: > > > > No, gjournal is a layer below the file system (think > > of it as a virtual disk drive) that does > journalling. > > You need to create a file system on top of gjournal. > > > Pawel added some necessary integration for UFS. > > > Since the gjournal is block level journaling, not file > system level journaling, can one journal be used to > cover two or more partitions? > > Example: > gjournal label -c ad0s4e ad0s4d > gjournal label -c ad0s4f ad0s4d > gjournal label -c ad0s4g ad0s4d > > newfs -J /dev/ad0s4e.journal > newfs -J /dev/ad0s4f.journal > newfs -J /dev/ad0s4g.journal > Unfortunately not, the most you can do is divide that one partition into more partitions and use each of those separately for each file system. Most of those limitations (journal size, usage, etc.) stem from the fact that gjournal is not "proper" file system journaling in the sense that it's implemented outside of the actual file system and is basically independent from it. A "proper" journalled UFS (like Sun's) would behave nicer.