From owner-freebsd-arch@FreeBSD.ORG Wed Oct 17 10:56:59 2007 Return-Path: Delivered-To: freebsd-arch@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 93D1316A417; Wed, 17 Oct 2007 10:56:59 +0000 (UTC) (envelope-from zec@icir.org) Received: from xaqua.tel.fer.hr (xaqua.tel.fer.hr [161.53.19.25]) by mx1.freebsd.org (Postfix) with ESMTP id 20DDD13C442; Wed, 17 Oct 2007 10:56:59 +0000 (UTC) (envelope-from zec@icir.org) Received: by xaqua.tel.fer.hr (Postfix, from userid 20006) id 757EE9B655; Wed, 17 Oct 2007 12:37:10 +0200 (CEST) X-Spam-Checker-Version: SpamAssassin 3.1.7 (2006-10-05) on xaqua.tel.fer.hr X-Spam-Level: X-Spam-Status: No, score=-4.3 required=5.0 tests=ALL_TRUSTED,AWL,BAYES_00 autolearn=ham version=3.1.7 Received: from [192.168.200.100] (zec2.tel.fer.hr [161.53.19.79]) by xaqua.tel.fer.hr (Postfix) with ESMTP id D079E9B64D; Wed, 17 Oct 2007 12:37:08 +0200 (CEST) From: Marko Zec To: freebsd-arch@freebsd.org Date: Wed, 17 Oct 2007 12:37:06 +0200 User-Agent: KMail/1.9.7 References: <470E5BFB.4050903@elischer.org> <20071016075255.GG61822@webcom.it> In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-2" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200710171237.07583.zec@icir.org> Cc: Ivan Voras Subject: Re: kernel level virtualisation requirements. X-BeenThere: freebsd-arch@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Discussion related to FreeBSD architecture List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 17 Oct 2007 10:56:59 -0000 On Wednesday 17 October 2007 00:54:21 you wrote: > Andrea Campi wrote: > > In para-virtualization you modify the kernel source in such a way > > that accesses to the hardware are instead translated into calls to > > the hypervisor. This means you could simply write device drivers > > for a "virtual network adapter", "virtual disk" etc. What this buys > > you is that you can have a full kernel (say 6.x) running as a > > hypervisor, and trimmed down kernels (say 7.x and several 6.x > > versions), compiled with only the virtual device drivers, running > > as additional VMs. > > > > WDYT? > > Well Xen does paravirtulization like you described (and I agree > something like that is more flexible then jails, if supported by > other operating systems). Actually, resource virtualization done at kernel level could offer great degree of flexiblity. Ideally, a modular virtualization framework would allow one to virtualize only the resources one needs, for example having a single process talking to several isolated networking domains, or having several processes bound to the same slot in a proportional share CPU scheduler, sharing or not sharing the same filesystem hierarchy etc. I think the thrust of this thread was in tackling people's imagination on how such a modular virtualization framework should look like, and which capabilities it should offer and which not. I.e. not get carried away in comparing kernel-level virtualization in general against Xen and alike, which are undoubtably very useful tools which have secured their place under the sun... Cheers, Marko > DragonflyBSD has its own flavor of > virtualization similar to user mode Linux, but it has greatly > diverged from FreeBSD so it't probably not trivially portable. > > Or do you mean something like this: > http://feanor.sssup.it/~fabio/freebsd/lkvm/ ?