From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 14192C433F5 for ; Mon, 31 Jan 2022 07:48:11 +0000 (UTC) Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-110-1r4f6T8_PGyq9-Pn7arXJQ-1; Mon, 31 Jan 2022 02:48:08 -0500 X-MC-Unique: 1r4f6T8_PGyq9-Pn7arXJQ-1 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id E26621006AA6; Mon, 31 Jan 2022 07:48:00 +0000 (UTC) Received: from colo-mx.corp.redhat.com (colo-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.20]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 065A91037F37; Mon, 31 Jan 2022 07:47:56 +0000 (UTC) Received: from lists01.pubmisc.prod.ext.phx2.redhat.com (lists01.pubmisc.prod.ext.phx2.redhat.com [10.5.19.33]) by colo-mx.corp.redhat.com (Postfix) with ESMTP id 1D6C11809CB8; Mon, 31 Jan 2022 07:47:45 +0000 (UTC) Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.rdu2.redhat.com [10.11.54.1]) by lists01.pubmisc.prod.ext.phx2.redhat.com (8.13.8/8.13.8) with ESMTP id 20V7lexL005829 for ; Mon, 31 Jan 2022 02:47:41 -0500 Received: by smtp.corp.redhat.com (Postfix) id B876440CFD18; Mon, 31 Jan 2022 07:47:40 +0000 (UTC) Received: from mimecast-mx02.redhat.com (mimecast07.extmail.prod.ext.rdu2.redhat.com [10.11.55.23]) by smtp.corp.redhat.com (Postfix) with ESMTPS id B46EE40CFD0F for ; Mon, 31 Jan 2022 07:47:40 +0000 (UTC) Received: from us-smtp-1.mimecast.com (us-smtp-delivery-1.mimecast.com [207.211.31.120]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 328683C02186 for ; Mon, 31 Jan 2022 07:47:40 +0000 (UTC) Received: from plutone.assyoma.it (host195-56-237-212.serverdedicati.aruba.it [212.237.56.195]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-249-cXOgo_a9NDiEIHMzoEnbog-1; Mon, 31 Jan 2022 02:47:37 -0500 X-MC-Unique: cXOgo_a9NDiEIHMzoEnbog-1 Received: from webmail.assyoma.it (localhost [IPv6:::1]) by plutone.assyoma.it (Postfix) with ESMTPA id 99F16DEBDF33; Mon, 31 Jan 2022 08:47:34 +0100 (CET) MIME-Version: 1.0 Date: Mon, 31 Jan 2022 08:47:34 +0100 From: Gionatan Danti To: LVM general discussion and development In-Reply-To: <30ba3f0683afb9c3b60d96ac0019ced4ce9bb5b8.camel@gathman.org> References: <6da8a7fc-4ca4-9c1d-c547-dcba827c5c99@gmail.com> <4bb347f0-b63b-d6f6-d501-1318053d0e56@gmail.com> <30ba3f0683afb9c3b60d96ac0019ced4ce9bb5b8.camel@gathman.org> User-Agent: Roundcube Webmail/1.4.13 Message-ID: X-Sender: g.danti@assyoma.it X-Mimecast-Impersonation-Protect: Policy=CLT - Impersonation Protection Definition; Similar Internal Domain=false; Similar Monitored External Domain=false; Custom External Domain=false; Mimecast External Domain=false; Newly Observed Domain=false; Internal User Name=false; Custom Display Name List=false; Reply-to Address Mismatch=false; Targeted Threat Dictionary=false; Mimecast Threat Dictionary=false; Custom Threat Dictionary=false X-Scanned-By: MIMEDefang 2.84 on 10.11.54.1 X-loop: linux-lvm@redhat.com Cc: Zdenek Kabelac Subject: Re: [linux-lvm] LVM performance vs direct dm-thin X-BeenThere: linux-lvm@redhat.com X-Mailman-Version: 2.1.12 Precedence: junk Reply-To: LVM general discussion and development List-Id: LVM general discussion and development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: linux-lvm-bounces@redhat.com Errors-To: linux-lvm-bounces@redhat.com X-Scanned-By: MIMEDefang 2.84 on 10.5.11.22 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=linux-lvm-bounces@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Il 2022-01-30 22:39 Stuart D. Gathman ha scritto: > I use LVM as flexible partitions (i.e. only classic LVs, no thin pool). > Classic LVs perform like partitions, literally using the same driver > (device mapper) with a small number of extents, and are if anything > more recoverable than partition tables. We used to put LVM on bare > drives (like AIX did) - who needs a partition table? But on Wintel, > you need a partition table for EFI and so that alien operating systems > know there is something already on a disk. Classical (fat) LVs are rock solid, but how do you cope with fast (maybe rolling) snapshotting? This is the main selling point of thinlvm. > Since we use LVs like partitions - mixing with btrfs is not an issue. > Just use the LVs like partitions. I haven't tried ZFS on linux - it > may have LVM like features that could fight with LVM. ZFS would be my > first choice on a BSD box. I broadly use ZFS - and yes, it is a wonderful tools. Than said, it has its own gotcha. For example: - snapshot rollback is a destructive operation (ie: after rollback, you permanently lose the current filesystem state); - clones (writable snapshots) depend on the read-only base image (ie: on the original snapshot), which you can not delete until you have its clones around. Moreover, snapshotting/cloning a ZFS dataset (or volume) does not appear to be significantly faster then LVM - sometime it requires ~1s, depending on the load. > We do not use LVM raid - but either run mdraid underneath, or let btrfs > do it's data duplication thing with LVs on different spindles. I always found btrfs very underperforming when facing random rewrite workloads as VMs and DBs. Can I ask your experience? Regards. -- Danti Gionatan Supporto Tecnico Assyoma S.r.l. - www.assyoma.it email: g.danti@assyoma.it - info@assyoma.it GPG public key ID: FF5F32A8 _______________________________________________ linux-lvm mailing list linux-lvm@redhat.com https://listman.redhat.com/mailman/listinfo/linux-lvm read the LVM HOW-TO at http://tldp.org/HOWTO/LVM-HOWTO/