From owner-freebsd-questions@freebsd.org Fri Feb 14 04:08:48 2020 Return-Path: Delivered-To: freebsd-questions@mailman.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.nyi.freebsd.org (Postfix) with ESMTP id D71FE23F7DA for ; Fri, 14 Feb 2020 04:08:48 +0000 (UTC) (envelope-from dpchrist@holgerdanske.com) Received: from holgerdanske.com (holgerdanske.com [IPv6:2001:470:0:19b::b869:801b]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client CN "holgerdanske.com", Issuer "holgerdanske.com" (not verified)) by mx1.freebsd.org (Postfix) with ESMTPS id 48Jfy80KsKz41hk for ; Fri, 14 Feb 2020 04:08:47 +0000 (UTC) (envelope-from dpchrist@holgerdanske.com) Received: from 99.100.19.101 ([99.100.19.101]) by holgerdanske.com with ESMTPSA (ECDHE-RSA-AES128-GCM-SHA256:TLSv1.2:Kx=ECDH:Au=RSA:Enc=AESGCM(128):Mac=AEAD) (SMTP-AUTH username dpchrist@holgerdanske.com, mechanism PLAIN) for ; Thu, 13 Feb 2020 20:08:31 -0800 Subject: Re: some questions about disk partitioning and filesystems and booting To: freebsd-questions@freebsd.org References: <20200213150229.GC14144@bastion.zyxst.net> From: David Christensen Message-ID: <091dd3af-7b99-267f-7d04-541b6d651926@holgerdanske.com> Date: Thu, 13 Feb 2020 20:08:27 -0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.4.1 MIME-Version: 1.0 In-Reply-To: <20200213150229.GC14144@bastion.zyxst.net> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit X-Rspamd-Queue-Id: 48Jfy80KsKz41hk X-Spamd-Bar: -- Authentication-Results: mx1.freebsd.org; dkim=none; dmarc=none; spf=none (mx1.freebsd.org: domain of dpchrist@holgerdanske.com has no SPF policy when checking 2001:470:0:19b::b869:801b) smtp.mailfrom=dpchrist@holgerdanske.com X-Spamd-Result: default: False [-2.75 / 15.00]; ARC_NA(0.00)[]; RCVD_VIA_SMTP_AUTH(0.00)[]; NEURAL_HAM_MEDIUM(-0.99)[-0.991,0]; FROM_HAS_DN(0.00)[]; TO_MATCH_ENVRCPT_ALL(0.00)[]; IP_SCORE(-1.66)[ipnet: 2001:470::/32(-4.65), asn: 6939(-3.58), country: US(-0.05)]; MIME_GOOD(-0.10)[text/plain]; TO_DN_NONE(0.00)[]; PREVIOUSLY_DELIVERED(0.00)[freebsd-questions@freebsd.org]; AUTH_NA(1.00)[]; RCPT_COUNT_ONE(0.00)[1]; NEURAL_HAM_LONG(-1.00)[-1.000,0]; DMARC_NA(0.00)[holgerdanske.com]; R_SPF_NA(0.00)[]; FROM_EQ_ENVFROM(0.00)[]; R_DKIM_NA(0.00)[]; MIME_TRACE(0.00)[0:+]; ASN(0.00)[asn:6939, ipnet:2001:470::/32, country:US]; MID_RHS_MATCH_FROM(0.00)[]; RCVD_TLS_ALL(0.00)[]; RCVD_COUNT_TWO(0.00)[2] X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 14 Feb 2020 04:08:48 -0000 On 2020-02-13 07:02, tech-lists wrote: > Hi, > > [1] > When a new (12.x) amd64 system is installed, the partition defaults to > MBR. I > normally use this as it's the default. I don't run mixed-OS systems; > they are > all freebsd. But I understand that GPT is newer or "better"? > > If GPT is "better" then why is it not the default? > > My use case is always ufs for the OS and zfs for data. Would it be > "better" to > use GPT when installing a system? I put my operating system installations on single, small 2.5" SATA SSD's and I put 2.5" SATA trayless disk bays in my computers. This both facilitates imaging and allows me to mix and match as required. For FreeBSD, I use ZFS throughout. Not all of my computers support booting from GPT, so I use MBR for system drives. The default FreeBSD installer wants to use the entire disk, so I hacked the memstick installer and/or choose the following in the installer: - 1 MiB alignment for everything - 14 GiB slice - 2 GiB boot partition, copies=2 - 2 GiB swap partition, mirrored - 10 GiB root partition, copies=2 The most obvious downside is that MBR does not support labels. So, the FreeBSD boot system uses device node names. This means I have to ensure that the system drive is always ada0 -- during install, whenever I move the drive to another machine, and whenever I add or remove drives or controllers. If the drive comes up as the wrong device node, I move SATA cables around. > [2] > The bsdinstaller defaults to 4GB swap. Isn't this insufficient on a 32GB > system? Doesn't swap need to be 2x RAM on a fast disk? > > The next install I do I'm thinking of making 2x 32GB swap partitions. These > being on the same SSD as the base OS. Would you consider this to be > suboptimal, and if so, why? In the past, I tried running systems without swap. They crashed. My current preference is to have plenty of RAM and a nominal swap partition. One possibility might be to install with a small swap partition now and put a large dummy partition at the end in case you need more swap later. Then again, if your workload does require a lot of swap, you could add a dedicated swap device and disable the swap partition on the system drive. David