From owner-freebsd-virtualization@freebsd.org Mon Mar 21 18:01:24 2016 Return-Path: Delivered-To: freebsd-virtualization@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 0A8A6AD88BC for ; Mon, 21 Mar 2016 18:01:24 +0000 (UTC) (envelope-from lists@jnielsen.net) Received: from webmail2.jnielsen.NET (webmail2.jnielsen.net [50.114.224.20]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client CN "webmail2.jnielsen.net", Issuer "freebsdsolutions.net" (not verified)) by mx1.freebsd.org (Postfix) with ESMTPS id E1405C41 for ; Mon, 21 Mar 2016 18:01:23 +0000 (UTC) (envelope-from lists@jnielsen.net) Received: from jnielse-ml.domo.com (50-207-241-62-static.hfc.comcastbusiness.net [50.207.241.62]) (authenticated bits=0) by webmail2.jnielsen.NET (8.15.2/8.15.1) with ESMTPSA id u2LI1Drl061806 (version=TLSv1 cipher=ECDHE-RSA-AES256-SHA bits=256 verify=NO); Mon, 21 Mar 2016 12:01:16 -0600 (MDT) (envelope-from lists@jnielsen.net) X-Authentication-Warning: webmail2.jnielsen.NET: Host 50-207-241-62-static.hfc.comcastbusiness.net [50.207.241.62] claimed to be jnielse-ml.domo.com Content-Type: text/plain; charset=utf-8 Mime-Version: 1.0 (Mac OS X Mail 9.2 \(3112\)) Subject: Re: ZFS subvolume support inside Bhyve vm From: John Nielsen In-Reply-To: <56E211FE.2060700@redbarn.org> Date: Mon, 21 Mar 2016 12:01:09 -0600 Cc: =?utf-8?B?0KHQtdGA0LPQtdC5INCc0LDQvNC+0L3QvtCy?= , Sergei Mamonov , "freebsd-virtualization@freebsd.org" Content-Transfer-Encoding: quoted-printable Message-Id: <06FE3C97-1165-482E-8DC3-1B3A2D6C4A91@jnielsen.net> References: <56E206FE.3080000@redbarn.org> <56E211FE.2060700@redbarn.org> To: Paul Vixie X-Mailer: Apple Mail (2.3112) X-BeenThere: freebsd-virtualization@freebsd.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: "Discussion of various virtualization techniques FreeBSD supports." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 21 Mar 2016 18:01:24 -0000 > On Mar 10, 2016, at 5:31 PM, Paul Vixie wrote: >=20 > =D0=A1=D0=B5=D1=80=D0=B3=D0=B5=D0=B9 =D0=9C=D0=B0=D0=BC=D0=BE=D0=BD=D0=BE= =D0=B2 wrote: >> Hello! >>=20 >> Yes - zvols looks awesome. But what driver you use for it? >=20 > virtio-blk. >=20 >> And what >> about disk usage overhead in guest? >=20 > ufs on zvol is faster, either in the parent or a bhyve using = virtio-blk, than zfs. at least for writing, which is my dominant work = load. i expect that this is due to zfs's compression logic rather than = anything having to do with creating/extending files to accommodate = writes. >=20 >> virtio-blk doesnt support fstrim (ahci-hd support it, but slower? = "/At >> this point virtio-blk is indeed faster then ahci-hd on high IOPS/"). >> In linux && kvm we try used virtio-scsi driver with support fstrim, = but >> how I see it not availble now in 10-2 stable for bhyve. >> And I not lonely with this question - >> = https://lists.freebsd.org/pipermail/freebsd-virtualization/2015-March/0034= 42.html >=20 > i'm just going to live without fstrim until it's supported in = virtio-blk. i know that this option isn't available to everybody, but at = the moment storage is cheap enough to waste. At the risk of getting farther off-topic.. Virtio-blk can't and won't support fstrim. If/when bhyve were to have = virtio-scsi support that could work with trim, but last I was aware = there wasn't a whole lot of momentum in that direction. The virtual AHCI = controller in bhyve does support trim and performs remarkably well. = That's what I use for my vol-backed VMs and I haven't had any = complaints. Worth testing, IMO. JN