From owner-freebsd-questions@FreeBSD.ORG Mon Dec 22 16:47:38 2014 Return-Path: Delivered-To: freebsd-questions@freebsd.org Received: from chateau.d.if (localhost [IPv6:::1]) by hub.freebsd.org (Postfix) with ESMTP id D99155EF; Mon, 22 Dec 2014 16:47:36 +0000 (UTC) Received: from chateau.d.if (chateau.d.if [IPv6:::1]); by chateau.d.if (OpenSMTPD) with ESMTP id 656ce4b4; Mon, 22 Dec 2014 22:17:35 +0530 (IST) From: ashish@FreeBSD.org (Ashish SHUKLA) To: Nikos Vassiliadis Subject: Re: zvol vs plain file for VMs Organization: The FreeBSD Project References: <54947594.2060202@gmx.com> <86mw6ilvyf.fsf@chateau.d.if> <549801AF.5000208@gmx.com> X-Face: )vGQ9yK7Y$Flebu1C>(B\gYBm)[$zfKM+p&TT[[JWl6:]S>cc$%-z7-`46Zf0B*syL.C]oCq[upTG~zuS0.$"_%)|Q@$hA=9{3l{%u^h3jJ^Zl; t7 X-Uptime: 9:34PM up 33 mins, 3 users, load averages: 0.08, 0.16, 0.15 X-Operating-System: FreeBSD/FreeBSD 10.1-RELEASE/amd64 X-OpenPGP-Fingerprint: F682 CDCC 39DC 0FEA E116 20B6 C746 CFA9 E74F A4B0 X-Attribution: =?utf-8?B?4KSG4KS24KWA4KS3?= Organisation: The FreeBSD Project X-Hashcash: 1:20:141222:freebsd-questions@freebsd.org::wo1htolKGbRNu85x:000000000000000000000000000000000+Nk X-Hashcash: 1:20:141222:nvass@gmx.com::ID1dqn2B0e6gkg7Y:00002SXK X-Hashcash: 1:20:141222:ashish@freebsd.org::HGVqy9fKs3cS/RG5:00000000000000000000000000000000000000000006VhX Date: Mon, 22 Dec 2014 22:17:31 +0530 In-Reply-To: <549801AF.5000208@gmx.com> (Nikos Vassiliadis's message of "Mon, 22 Dec 2014 12:34:07 +0100") Message-ID: <86fvc7my1o.fsf@chateau.d.if> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/25.0.50 (amd64-portbld-freebsd10.1) Face: iVBORw0KGgoAAAANSUhEUgAAADAAAAAwBAMAAAClLOS0AAAAJ1BMVEWpqal/f39tbW1jY2Md HR2goKCenp6UlJROTk7////9/f35+fnT09ORJdieAAACVklEQVQ4jXXUP2vbQBQA8AvUTkgz5OzY Z0iGWhpS6BSrkECn0mvx0MEJ6AjtYrfoBCVDlD8naJYmNlRfwZq8+mkKlIZaGpJSYmP7Q/XkJDrJ Td8i/H68u3vHPaPufwLdf32AMA4A6GcAgvAamY1pOJiDIFqicTwLswDhfr3uxfFtkAY/GFHPMwzD 8zpnACmIOnE6js7rQb+v4NJrG9od0C+QgpHMy5jBewV+UDSMWiw1Y4fWfyV7+NGFzDsYa3pth9LJ Q4XvXxFHcJRvHOmygn5NAEabnDcQQguarnfoiwSCJ99jmKKcphsZONmWsDK9Ro7cvZOCtQdg8nje egLhc2LNlkLmsezzTFUUy5w18ocox/f0LaLgJy0zO75zk+9pp85GAj36xjqhdI0y3tq2m4dqqcWX zQWBTz8L1irvolXV4J+3q7eCDgVnttjNq6X8H+9KOZsuNk1uCzx8pSp+E9HImfJOTLdcGqo+YKnG EIovizkEn48V7BO+ch2DXcD4ENSpWiU+q8hjjbgTBZCXnZtyj0Ws4Q1Q0B2WXFtYZo65Bbyeeldw RS6qFueM80LlLA29YlVwGRYvFD+kwI/0O+A2PlpOP9GwslUVciHuYGechuBTp922YiDZCrghTknm XSyOM+D3aoRZlo0Jb42zY7DN4p2x4AeZ+QAYutx1sHwTHzMT5cMNduQ9yW3GczN4KZ86kb0c9O8T yXDeFqpl2fryPEAYGXIlezAPXYh2NgVr/gvdoHIuDwuPwOhcWE8f8mmICq41eATkn8x0kuRTIKcB wE9+/QUtiiAnYcaN7wAAAABJRU5ErkJggg== MIME-Version: 1.0 Content-Type: multipart/signed; boundary="=-=-="; micalg=pgp-sha512; protocol="application/pgp-signature" Cc: Ashish SHUKLA , freebsd-questions@freebsd.org X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.18-1 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 22 Dec 2014 16:47:38 -0000 --=-=-= Content-Type: text/plain Content-Transfer-Encoding: quoted-printable On Mon, 22 Dec 2014 12:34:07 +0100, Nikos Vassiliadis said: | On 12/20/14 06:41, Ashish SHUKLA wrote: || On Fri, 19 Dec 2014 19:59:32 +0100, Nikos Vassiliadis sa= id: || | Hi, ||=20 || | I have to convert a mail server to a VM and I don't know what kind of || | storage to use, a plain file or a zvol? ||=20 || | Are there any pros in using ZVOLs instead of plain files? ||=20 || | Thanks, Nikos ||=20 || I don't use FreeBSD for VMs, but theoretically plain file will have file= system || overhead which ZVOL won't. ||=20 || HTH ||=20 | Hi, | Thank you for your reply Ashish! | When you say overhead, you mean overhead on disk or in RAM? could you | explain a bit more? Overhead as in, read/writes to file will go through filesystem driver to bl= ock devices, which involves traversing filesystem structures, compared to ZVOL which is likely to be contiguous and is exposed as a block device. HTH =2D-=20 Ashish SHUKLA | GPG: F682 CDCC 39DC 0FEA E116 20B6 C746 CFA9 E74F A4B0 Sent from my Emacs --=-=-= Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v2 iQIcBAEBCgAGBQJUmEskAAoJEMdGz6nnT6SwtzYQAJ66q2994o7pzccVOXvGr3Xm Q8Ww7+80sBYCA/BOkyQuHJElj13P8cGCcgLrcvJ8P9GHx/YIKz3eWtJ+55aRvOhY 4SGvRl9il0pjEFLqIBii/Dd5t34AG3x9X0bgRuaovPIwlNtFGwlEa8NZwNVhfQdA xDMVGtnGyxKRartpIf+Eo06sv1T80jvsmZIbSK6sx9CW0IsxE4gOanK4GyQPskHH dqwIgGx1K1of66wmitzOCe8H7OzPVzKy7dRMRDXb/2MiubTgM/61Co41jI0oK+gD liqQO4eDh+IvkU3x5wJnvIqbscn5St5F20wM/PpBYpSrE1p2MdIHebXt1mD2EWlP 8mY6gnekOQRwCpP+es48ml1wJQFz3Z3/sBN54FuIc/TUTbHxLGkQCa0HT2VORc/M vMOamZJhdt8tur+0MJj0VGOhW+IN4R8iQjEWnCrF8GxfPJWCeRuQ8wtkXkvujlon 531X5NNxdehbmxkjsnAK/j/xqgqSSGFvM/uIV3DYXGcvjlPvF+K6NiABgiklCweU bjPzDkhxqQDow3LIBLyoIuIeqQq5pVezpwuX/Vlc352wEljJqwCj1Rsh0227ZdRf GhF9ZF+JRoh75s4j9aBrx/7uvfT4ZWAJiE9dADLDwkAreqJnibjKqJNJmB9eSieG tYMD1wsNer4LBxcA69HC =gQnB -----END PGP SIGNATURE----- --=-=-=--