From mboxrd@z Thu Jan 1 00:00:00 1970 From: Rusty Russell Subject: Re: [PATCH/RFC 7/9] Virtual network guest device driver Date: Mon, 14 May 2007 12:39:15 +1000 Message-ID: <1179110355.23513.179.camel@localhost.localdomain> References: <1178903957.25135.13.camel@cotte.boeblingen.de.ibm.com> <1178904965.25135.34.camel@cotte.boeblingen.de.ibm.com> <13426df10705111244w1578ebedy8259bc42ca1f588d@mail.gmail.com> <46457EF9.2070706@de.ibm.com> <64F9B87B6B770947A9F8391472E032160BC74612@ehost011-8.exch011.intermedia.net> <4647257F.4020900@codemonkey.ws> <64F9B87B6B770947A9F8391472E032160BC74675@ehost011-8.exch011.intermedia.net> <4647418A.2040201@codemonkey.ws> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: Jimi Xenidis , Christian Borntraeger , jmk-zzFmDc4TPjtKvsKVC3L/VUEOCMrvLtNR@public.gmane.org, Herbert Xu , carsteno-tA70FqPdS9bQT0dZR+AlfA@public.gmane.org, mschwid2-23VcF4HTsmIX0ybBhKVfKdBPR1lH4CV8@public.gmane.org, kvm-devel-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org To: Anthony Liguori Return-path: In-Reply-To: <4647418A.2040201-rdkfGonbjUSkNkDKm+mE6A@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: kvm-devel-bounces-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org Errors-To: kvm-devel-bounces-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org List-Id: kvm.vger.kernel.org On Sun, 2007-05-13 at 11:49 -0500, Anthony Liguori wrote: > Dor Laor wrote: > > Furthermore, > > > >> the plan is to completely rearchitect the netback/netfront protocol for > >> the next Xen release (this effort is referred to netchannel2). > > It's looks like generalizing all the level 0,1,2 features plus > > performance optimizations. It's not something we couldn't upgrade to. > > I'm curious what Rusty thinks as I do not know nearly enough about the > networking subsystem to make an educated statement here. Would it be > better to just try and generalize netback/netfront or build something > from scratch? Could the lguest driver be generalized more easily? In turn, I'm curious as to Herbert's opinions on this. The lguest netdriver has only two features: it's small, and it does multi-way inter-guest networking as well as guest<->host. It's not clear how much the latter wins in real life over a point-to-point comms system. My interest is in a common low-level transport. My experience is that it's easy to create an efficient comms channel between a guest and host (ie. one side can access the others' memory), but it's worthwhile trying for a model which transparently allows untrusted comms (ie. hypervisor-assisted to access the other guest's memory). That's easier if you only want point-to-point (see lguest's io.c for a more general solution). Cheers, Rusty. ------------------------------------------------------------------------- This SF.net email is sponsored by DB2 Express Download DB2 Express C - the FREE version of DB2 express and take control of your XML. No limits. Just data. Click to get it now. http://sourceforge.net/powerbar/db2/