From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from firstgate.proxmox.com (firstgate.proxmox.com [212.224.123.68]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by lists.proxmox.com (Postfix) with ESMTPS id E9FA071E12 for ; Wed, 30 Jun 2021 15:40:57 +0200 (CEST) Received: from firstgate.proxmox.com (localhost [127.0.0.1]) by firstgate.proxmox.com (Proxmox) with ESMTP id D51921A296 for ; Wed, 30 Jun 2021 15:40:27 +0200 (CEST) Received: from mail-yb1-xb2a.google.com (mail-yb1-xb2a.google.com [IPv6:2607:f8b0:4864:20::b2a]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by firstgate.proxmox.com (Proxmox) with ESMTPS id 96A841A27F for ; Wed, 30 Jun 2021 15:40:25 +0200 (CEST) Received: by mail-yb1-xb2a.google.com with SMTP id k184so4974008ybf.12 for ; Wed, 30 Jun 2021 06:40:25 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to; bh=MKCWxGx/2lWRlxjScyjHpQGWr31XeH4wvlT/04au0+A=; b=Kht0QhX6m+QdxoBN9rvDyNM7ishE3o1JmbsAafA+B3OHWKRUDq80EstG00Hf2kyula Qx/FWUXpksr1BkN81exE8qVEXzr0JtRGwcWD83pQYZB4vCXRpNU1P5iW2U41e0HfV9O9 SxbbJ8Y5wBDU7V+MtBMw7OKKphOcUpQZGgJrk+8ZHFdOwxDY3Cl+AiD4V9Uv/uyhgMjn kyb5Ee5i46QaaMMgkqYA7IOMn7qFtZN+SkAP9j1a7JKq5mGrouhlSvsZUlSj47tgPNh1 +6dw4ePhqa1x406WuSx4TcMQfX6xLJzoXBHL/LEbI4gn/ufxeg27mat6trAouY+W93AN cyDw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to; bh=MKCWxGx/2lWRlxjScyjHpQGWr31XeH4wvlT/04au0+A=; b=o5Anzc2vHFjB6KJLxjQAG/UAS3NurTdcKgUxhBPjEtu7pLVcU2AEYnV4wG7AFXGXmg 2BrlkwJBeVc8zlGJ8TGZe28A4daD6soZLjCYiw9HdZc5riMuyFvYZnKoqT1bQH5drFCo L08Jq7R1AxyMQGdSH4Wfa2SNwTsrRzv6/GeQWDrLE7klDWvVaid0kenPwektJlEHGyRU vanvpdOVfKVaknE7bojIrFimfYmK+DeYOwELmLzBl8YD3Mz8lug46Br9Sj+68BnKhndz 424+DJSG32GCGPCiJGiPnyaOaBJoq0HJtDGd7BqR4zyMH2L1pLmSMuAWeoBEHXJquJtM 0Ypw== X-Gm-Message-State: AOAM532jNthp4OAnfdRctSD/NJgar2Zvw6J5pe0wBWmGqN48AlQEougi gDFcjWuKrzuz28gWInidjz599IqpbView8CBJLK3RPTq X-Google-Smtp-Source: ABdhPJzA1I0w2dYXg9OmiaBG8xCoaP0nfH2whbJ50xVLuYooPZvQ+rdh+NzCKquPOEMzFXW9H0rHSyGqL+alJXwvUe8= X-Received: by 2002:a5b:4c6:: with SMTP id u6mr46924467ybp.31.1625060417765; Wed, 30 Jun 2021 06:40:17 -0700 (PDT) MIME-Version: 1.0 References: <20210630092847.GG3262@sv.lnf.it> In-Reply-To: <20210630092847.GG3262@sv.lnf.it> From: "Yanni M." Date: Wed, 30 Jun 2021 14:40:06 +0100 Message-ID: To: Proxmox VE user list X-SPAM-LEVEL: Spam detection results: 0 AWL 1.000 Adjusted score from AWL reputation of From: address BAYES_00 -1.9 Bayes spam probability is 0 to 1% DKIM_SIGNED 0.1 Message has a DKIM or DK signature, not necessarily valid DKIM_VALID -0.1 Message has at least one valid DKIM or DK signature DKIM_VALID_AU -0.1 Message has a valid DKIM or DK signature from author's domain DKIM_VALID_EF -0.1 Message has a valid DKIM or DK signature from envelope-from domain FREEMAIL_ENVFROM_END_DIGIT 0.25 Envelope-from freemail username ends in digit FREEMAIL_FROM 0.001 Sender email is commonly abused enduser mail provider HTML_MESSAGE 0.001 HTML included in message POISEN_SPAM_PILL_4 0.1 random spam to be learned in bayes RCVD_IN_DNSWL_NONE -0.0001 Sender listed at https://www.dnswl.org/, no trust SPF_HELO_NONE 0.001 SPF: HELO does not publish an SPF Record SPF_PASS -0.001 SPF: sender matches SPF record URIBL_BLOCKED 0.001 ADMINISTRATOR NOTICE: The query to URIBL was blocked. See http://wiki.apache.org/spamassassin/DnsBlocklists#dnsbl-block for more information. [lanostrafamiglia.it, proxmox.com] Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Content-Filtered-By: Mailman/MimeDel 2.1.29 Subject: Re: [PVE-User] Guest LVM2 overhead/usefulness for thin storages (Ceph, ZFS) X-BeenThere: pve-user@lists.proxmox.com X-Mailman-Version: 2.1.29 Precedence: list List-Id: Proxmox VE user list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 30 Jun 2021 13:40:58 -0000 Personally I favor the flexibility that LVM offers when it comes to creating/resizing volumes (growing/shrinking), most of times without even needing to reboot the vm. Even if it's possible to do the same with disk partitioning, it's not as trivial as with lvm (hence why it was invented in the first place). Having to create a new vdisk on the host for each individual volume that you might need for the guest in the future - even though possible - it does not look as clean solution as doing all these, with lvm, within the guest. The overhead of the lvm is minimal and the discard/trim should be already enabled by default. Special care should be taken when using ThinLVM to avoid situations where the pools get full etc (same apply when used at the host level). Apart from that, it does not require any special administration skills, apart from familiarity with lvm tools obviously. To be clear, I'm not defending lvm in here. Both your and this method are ok. It's all about with what each person is familiar with and how each organise their work. On Wed, 30 Jun 2021 at 10:29, Marco Gaiarin wrote: > > A collegue here came from the old school of 'LVM everything', that > surely make sense for 'phisical servers'. > > Also, point me that make sense also for some 'virtual servers' (or > better, 'virtual storage') setup. > EG, considering a SAN, splitting virtual volumes in predefined chunks > (1/2TB) and 'recombine' them via LVM in the guest, permit to move > around smaller volumes, transparently for the guest. > > > But if we came to 'modern', thin storage, like ZFS or Ceph, this still > make sense? > Seems 'no' to me, seems to me only useful to add another layer of > abstraction... and the same functionality can be achived splitting data > in virtual disks as if was volumes, format with a single partition per > disk, and eventually extend the disk... > > And, this layer, how does it 'cost'? Not only in the term of > performance, but also functionality... eg, 'trim' can traverse correctly > all the layers? > > > I hope i was clear. Thanks. > > > PS: i've tried to look at the wiki but found nothing; if i've missed > something, point me to the doc! > > -- > dott. Marco Gaiarin GNUPG Key ID: > 240A3D66 > Associazione ``La Nostra Famiglia'' > http://www.lanostrafamiglia.it/ > Polo FVG - Via della Bont=C3=A0, 7 - 33078 - San Vito al Taglia= mento > (PN) > marco.gaiarin(at)lanostrafamiglia.it t +39-0434-842711 f > +39-0434-842797 > > Dona il 5 PER MILLE a LA NOSTRA FAMIGLIA! > http://www.lanostrafamiglia.it/index.php/it/sostienici/5x1000 > (cf 00307430132, categoria ONLUS oppure RICERCA SANITARIA) > > _______________________________________________ > pve-user mailing list > pve-user@lists.proxmox.com > https://lists.proxmox.com/cgi-bin/mailman/listinfo/pve-user > >