From owner-freebsd-hackers@freebsd.org Tue Sep 22 19:34:08 2015 Return-Path: Delivered-To: freebsd-hackers@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 663CAA062EA for ; Tue, 22 Sep 2015 19:34:08 +0000 (UTC) (envelope-from deco33000@yandex.com) Received: from forward20h.cmail.yandex.net (forward20h.cmail.yandex.net [IPv6:2a02:6b8:0:f35::a5]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client CN "forwards.mail.yandex.net", Issuer "Certum Level IV CA" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 1D69B128A; Tue, 22 Sep 2015 19:34:07 +0000 (UTC) (envelope-from deco33000@yandex.com) Received: from web20h.yandex.ru (web20h.yandex.ru [84.201.186.49]) by forward20h.cmail.yandex.net (Yandex) with ESMTP id 3FFB421263; Tue, 22 Sep 2015 22:33:55 +0300 (MSK) Received: from 127.0.0.1 (localhost [127.0.0.1]) by web20h.yandex.ru (Yandex) with ESMTP id 9238D13204F3; Tue, 22 Sep 2015 22:33:54 +0300 (MSK) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=yandex.com; s=mail; t=1442950434; bh=kYNVIbI0iCD9sUOsVhfsr1vDitJUj66cGeHSbkXmY9g=; h=From:To:Cc:In-Reply-To:References:Subject:Date; b=g3GwTW+Xtfyg5XYEEkjXLa3E3wyDrsnBFLbz3oksmZen9B34kxnbHFzgDSmNYTrRd +hd3SK+9cNbtv3OvYUdXL6QzaSq2inqMAnM24pjBUC7pJOCbFwdlbKfS/ys7i9znph z/BGAj+Fr6HZ5jWdLcsHWGiV1h1MXfuhBj4PR8uc= Received: by web20h.yandex.ru with HTTP; Tue, 22 Sep 2015 22:33:53 +0300 From: deco33000 Jog To: Wojciech Puchar Cc: Julian Elischer , "freebsd-hackers@freebsd.org" In-Reply-To: References: <730481442868585@web10h.yandex.ru> <5600F6D4.5040007@freebsd.org> <184701442916573@web12h.yandex.ru> Subject: Re: Virtual images and qemu MIME-Version: 1.0 Message-Id: <903401442950433@web20h.yandex.ru> X-Mailer: Yamail [ http://yandex.ru ] 5.0 Date: Tue, 22 Sep 2015 21:33:53 +0200 Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=koi8-r X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 22 Sep 2015 19:34:08 -0000 You are right, and I understand the paramount of virtualization. Hence my use of it now. But it doesn't change a hair of my position: I hate it but still use it. --š Jog 22.09.2015, 21:29, "Wojciech Puchar" : >> šNow it is fully working. I switched to virtualbox and chose a nat paravirt network. > > anyway FreeBSD 10.2 works fine under qemu - both amd64 and i386. tested. > Anyway i never used qcow2 images, always raw. > >> šI really hate virtualization but will bear with it anyway. > > instead of hate it's better to understand. > > Cases where virtualization is useful: > > - quick test of operating system (probably your case) > - OS/kernel development - avoids reboot as well as provide freeze and > memory dump. > - when you have to run more than 1 different OS on one machine. For > example: FreeBSD server but needs to run some server software under windows. Run > windows virtual machine on this server with this software in it. > - preparing software disk image for different architecture (often used > be me for FreeBSD/mips, qemu on fast PC runs faster than actual machine > and it's easier). > - recovery of data from disks or disk images > - may be few more. > > Cases where it is not useful, or suboptimal: > > - running multiple images of same unix system (eg. FreeBSD, linux) on one > computer. Use jails or similar mechanism under other unix-alike. > - magic way to enhance security. No it isn't. > - running windows desktops for terminal systems, one virtual machine per > user. Suboptimal and costly, run multiple users on single windows > computer. > - REALLY lots of other uses just because virtualization is popular. > > Virtualbox is MUCH faster, qemu is much more universal. Virtualization > always make performance overhead, and always bigger than authors claim. > Still - it is much better running some software set even with 50% overhead, than buying > separate machine that would be 1% utilized.