From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from lists.gentoo.org (pigeon.gentoo.org [208.92.234.80]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by finch.gentoo.org (Postfix) with ESMTPS id 2BED5158086 for ; Wed, 6 Oct 2021 19:50:45 +0000 (UTC) Received: from pigeon.gentoo.org (localhost [127.0.0.1]) by pigeon.gentoo.org (Postfix) with SMTP id 3267AE09F3; Wed, 6 Oct 2021 19:50:39 +0000 (UTC) Received: from mail-oi1-f176.google.com (mail-oi1-f176.google.com [209.85.167.176]) (using TLSv1.2 with cipher ECDHE-RSA-CHACHA20-POLY1305 (256/256 bits)) (No client certificate requested) by pigeon.gentoo.org (Postfix) with ESMTPS id C52D8E0908 for ; Wed, 6 Oct 2021 19:50:38 +0000 (UTC) Received: by mail-oi1-f176.google.com with SMTP id y201so5662392oie.3 for ; Wed, 06 Oct 2021 12:50:38 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to; bh=zm0ePXpuEes0YunaKRHpD4u8O05XJWtQPam8m79pFYg=; b=h5lwfwubJMw4KDTOwg19F3S4PpFRwKYxWRex7y3ywF+/YO/wFmsP5ielGdvuqCBy1Q dcxDf2XAHQIoH9/pWZ3zorqWZet/Ndr9kWVRtUK6c8RezDQnHcLripgoRshbLLTkvRS4 l2IBqmU2n2Ke6jYm2fD1yqbv6b5547ycOREhyxpwBbvHNAn/k+c0idKmbcHIiGOGdByi H4+o3joaRK9XAzEITTHtWoGsKBhiZ5A32hRM/DFPCUuubdfpcqg9o8/2sNxm8+H1FsaZ 4ttqT8yNAt7rM60HFyieSGCa/VeCAQ+dax2yOZ2SgqgK1mXyMrtVnAA1uEIkwCCJhcv5 dQdQ== X-Gm-Message-State: AOAM531Bha8uVE0sPJZVKyMDktUwXTgZijLQXUeNptbD2tcUn40I6xcN TszxCL7iCFV/jZnbjRj/DjDndcetA3QV2/fbQYK8cz41 X-Google-Smtp-Source: ABdhPJxekwTWB+MjOQbHQZCTZhRVqARefJfloL5jP+ttLduB4388/DOwUrtsp8ILdyWs8sO7aPOvHk0vSmsJfiO/G7M= X-Received: by 2002:a05:6808:1a04:: with SMTP id bk4mr105913oib.85.1633549837306; Wed, 06 Oct 2021 12:50:37 -0700 (PDT) Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-Id: Gentoo Linux mail X-BeenThere: gentoo-user@lists.gentoo.org Reply-to: gentoo-user@lists.gentoo.org X-Auto-Response-Suppress: DR, RN, NRN, OOF, AutoReply MIME-Version: 1.0 References: <3e528088-4325-202d-cd1f-f29efb42638d@gmail.com> In-Reply-To: From: Rich Freeman Date: Wed, 6 Oct 2021 15:50:27 -0400 Message-ID: Subject: Re: [gentoo-user] Hard drive pricing and the near future To: gentoo-user@lists.gentoo.org Content-Type: text/plain; charset="UTF-8" X-Archives-Salt: dd767d13-08fb-41fe-bb21-7b817905b947 X-Archives-Hash: 51e911b5a61088842fc6a75b92e5d562 On Wed, Oct 6, 2021 at 3:37 PM Laurence Perkins wrote: > I think what to look for there would be if there's a way to align the BTRFS chunks to the SMR blocks. There are definitely ways to implement filesystems that are more compatible with SMR. You basically want something like a log-based filesystem. A COW filesystem is actually a really good candidate as they don't do in-place writes ever, and all you need to do is defer block frees and garbage collect and so on to make it more log-based. One of the issues though is that these drives obfuscate how they work. The filesystem has no way to intentionally write to the CMR vs SMR regions. This is why drive-managed SMR really shouldn't be a thing. Host-managed SMR makes a LOT more sense, because then the filesystem can mitigate most of the issues and not end up fighting the drive firmware, whose behavior isn't even standardized. > But the manufacturers decided to continue manufacturing CBR disks for the surveillance industry, so I haven't had to worry about it just yet. There are lots of CMR drives out there. It is just that you have to be careful as nothing is well-documented and it is all subject to change. It is like trying to figure out how many channels a DIMM has or what its timing capabilities are. I saw a good price on an Exos drive and I believe those are all CMR. This is why I use slickdeals - you can set up searches and get alerts when a price drops. It also picks up stuff like Best Buy who often has some of the best prices on USB enclosures for whatever reason when they go on sale. -- Rich