From owner-freebsd-stable@FreeBSD.ORG Wed Nov 19 14:50:51 2014 Return-Path: Delivered-To: freebsd-stable@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id C452983B for ; Wed, 19 Nov 2014 14:50:51 +0000 (UTC) Received: from mail.ijs.si (mail.ijs.si [IPv6:2001:1470:ff80::25]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 74360B0 for ; Wed, 19 Nov 2014 14:50:51 +0000 (UTC) Received: from amavis-proxy-ori.ijs.si (localhost [IPv6:::1]) by mail.ijs.si (Postfix) with ESMTP id 3jjRls4St2z7S for ; Wed, 19 Nov 2014 15:50:49 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ijs.si; h= user-agent:message-id:references:in-reply-to:organization :subject:subject:from:from:date:date:content-transfer-encoding :content-type:content-type:mime-version:received:received :received:received; s=jakla4; t=1416408646; x=1419000647; bh=WNm 1ES5MEB7bR/vjuFQHSMR5s6wmEDeSuuXJKR3P62k=; b=PyxGEqzisbNIMzNVuzY VxtYy7op/fkrtiD1SsdGE1+h6iDgBADuitPkupFry9Gnn/vZMwq8kBQP4sSHca8C dV7TPUcIuhSfj7L06ty4iruY2SxvCCcdqOBEgkTiF2tBhz9zCVVEz6scSVgDiNjw hX6lPPCJzVWRO4KCTdudBBtA= X-Virus-Scanned: amavisd-new at ijs.si Received: from mail.ijs.si ([IPv6:::1]) by amavis-proxy-ori.ijs.si (mail.ijs.si [IPv6:::1]) (amavisd-new, port 10012) with ESMTP id rbCClqf7tzo3 for ; Wed, 19 Nov 2014 15:50:46 +0100 (CET) Received: from mildred.ijs.si (mailbox.ijs.si [IPv6:2001:1470:ff80::143:1]) by mail.ijs.si (Postfix) with ESMTP for ; Wed, 19 Nov 2014 15:50:46 +0100 (CET) Received: from neli.ijs.si (neli.ijs.si [IPv6:2001:1470:ff80:88:21c:c0ff:feb1:8c91]) by mildred.ijs.si (Postfix) with ESMTP id 3jjRlp1lPKz9p for ; Wed, 19 Nov 2014 15:50:46 +0100 (CET) Received: from neli.ijs.si ([2001:1470:ff80:88:21c:c0ff:feb1:8c91]) by neli.ijs.si with HTTP (HTTP/1.1 POST); Wed, 19 Nov 2014 15:50:46 +0100 MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII; format=flowed Content-Transfer-Encoding: 7bit Date: Wed, 19 Nov 2014 15:50:46 +0100 From: Mark Martinec To: freebsd-stable@freebsd.org Subject: Re: 10.1 fresh install and 4k alignment Organization: J. Stefan Institute In-Reply-To: References: Message-ID: <27d8222a2b617ac515c38a0023151320@mailbox.ijs.si> X-Sender: Mark.Martinec+freebsd@ijs.si User-Agent: Roundcube Webmail/1.0.3 X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.18-1 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 19 Nov 2014 14:50:51 -0000 > None of the start sector numbers is a multiple of 8, neither are the > end sectors a multiple of 8 minus 1. > > So the pool uses a 4k block size but it starts on an odd multiple of 2k > on the platter - do I see this correctly? > [...] > Is this a bug in the installer? Will I still have to layout the disks > manually if I want 4k alignment? What's a good offset for the first > partition in this case? Anything bigger than 34 that's a multiple of > 8 - 40 or 64? >> "GPT partitions not 4k aligned by 10.1-RC1 installer" >> >> https://lists.freebsd.org/pipermail/freebsd-stable/2014-October/080509.html I consider a sensible alignment nowadays to be '-a 1m' for any GPT partition, including freebsd-boot. If one is very short on space and not on an SSD, one may save 0.5 MB by aligning freebsd-boot on -a 512k and everything else on '-a 1m': gpart add -t freebsd-boot -a 1m -s 512k -i 1 ... gpart add -t freebsd-swap -a 1m -i 2 ... ... or: gpart add -t freebsd-boot -a 512k -s 512k -i 1 ... gpart add -t freebsd-swap -a 1m -i 2 ... ... Mark