On Thu, Feb 25, 2010 at 04:53:56PM -0600, John Goerzen wrote: > Hi folks, > > There was a thread here a little while back about the status of Xen in > future Debian releases. It left me rather confused, and I'm hoping to > find some answers (which I will then happily document in the wiki). > > According to http://wiki.debian.org/SystemVirtualization : > > "Qemu and KVM - Mostly used on Desktops/Laptops" > Yes - but also the only game in town for cross platform emulation.
KVM is shaping up well and appears to be very well supported by Red Hat. > "VirtualBox - Mostly used on Desktops/Laptops" Who knows what will happen to this now that Oracle own it? It's possible it will be merged in one of their other products like Virtual Iron. > > "Xen - Provides para-virtualization and full-virtualization. Mostly used > on servers. Will be abandoned after squeeze." > I think that the problem here is that Xen isn't mainstream in the kernel. It takes a long time for a Xen-ified kernel to come out and any distribution supporting it has to carry a heavy patch burden. Xen doesn't keep anywhere current in terms of kernel - if we release Squeeze this year with kernel 2.6.3*, Debian will have to maintain all the patches / "forward port" them to 2.6.32 or 2.6.33 as was done with 2.6.2*. Red Hat will support Xen for Red Hat Enterprise Linux 5.x, for example, primarily because it was there for 5.0 on 2.6.18. Red Hat now have a 7 year commitment to a support lifecycle based on one kernel release. The Red Hat kernel is already heavily patched (and takes 18 months or so to release - by the time they stop supporting 5.x, the code will be almost 9 years old) - and the back patching of security fixes and requested features through the support lifecycle is a nightmare for them. I'd be slightly surprised if they commit to Xen through the lifecycle of their version 6.x. > The Xen page on the wiki makes no mention of this. > > So, I am wondering about our direction in this way: > > 1) Will a squeeze system be able to run the Xen hypervisor? A Xen dom0? > > 2) Will a squeeze system be able to be installed as a Xen domU with a > lenny dom0? What about squeeze+1? > > 3) What will be our preferred Linux server virtualization option after > squeeze? Are we confident enough in the stability and performance of > KVM to call it such? (Last I checked, its paravirt support was of > rather iffy stability and performance, but I could be off.) > > 3a) What about Linux virtualization on servers that lack hardware > virtualization support, which Xen supports but KVM doesn't? > Which servers that lack hardware virtualisation support - pretty much everything made in the last two or three years has it. For servers, specifically, the likelihood is that - Lenny has a 2 year life + 1 year, Squeeze has ? year life + 1 year - by the time you get to Squeeze + 1 anything that doesn't will be almost ten years old. QEMU will work. Non-Intel - ARM, PPC ... may be another matter. > 4) What will be our preferred server virtualization option for non-Linux > guests after squeeze? Still KVM? > > 5) Do we recommend that new installations of lenny or of squeeze avoid > Xen for ease of upgrading to squeeze+1? If so, what should they use? > New Squeeze - use KVM? New Lenny - whatever you want, because at this point you have (days until release of Squeeze + 1 year) to find an alternative. > 6) Are we communicating this to Debian users in some way? What can I do > to help with this point? > > Thanks, > > -- John > > Just my 0.02c AndyC > -- > To UNSUBSCRIBE, email to debian-devel-requ...@lists.debian.org > with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org > Archive: http://lists.debian.org/4b86ff84.4020...@complete.org -- To UNSUBSCRIBE, email to debian-devel-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org Archive: http://lists.debian.org/20100226070159.ga18...@galactic.demon.co.uk