Comments on: The Future of Xen http://etbe.coker.com.au/2008/05/02/the-future-of-xen/ Linux, politics, and other interesting things Wed, 08 Oct 2008 02:29:34 +0000 http://wordpress.org/?v=2.6.2 By: geb http://etbe.coker.com.au/2008/05/02/the-future-of-xen/#comment-13470 geb Sat, 03 May 2008 12:33:04 +0000 http://etbe.coker.com.au/?p=578#comment-13470 thx to intel, the new bios even broke systems with 4GB, so yes it's an bios issue which is there since last year thx to intel, the new bios even broke systems with 4GB, so yes it’s an bios issue which is there since last year

]]> By: etbe http://etbe.coker.com.au/2008/05/02/the-future-of-xen/#comment-13467 etbe Sat, 03 May 2008 11:03:56 +0000 http://etbe.coker.com.au/?p=578#comment-13467 tbl: Thanks for the suggestion, it's interesting to know how other Unix systems work with Xen. Generally I don't have enough time to learn about the other distributions of Linux, let alone other Unix systems. Stefano: My understanding of OpenVZ is that it's like VServer in it's design. This doesn't work for some of the things I want to do as I want to run different kernel versions as DomU's (or equivalent). Jeff: Thanks, I should have tried that before upgrading to Unstable. specialj: My laptop doesn't get much travel nowadays, mostly it's moved between desks and even when running Xen the batteries last the duration of the journey. But you are correct that it is a problem with Xen and a win for KVM. Anon: I liked it when they had different names, Pentium 3, Pentium 4, Pentium D, and different clock speeds and cache sizes within that range. They stuffed it up a little by releasing both 32bit and 64bit chips under the name "Celeron D" and then abandoned it entirely in recent times. geb: That sounds like a BIOS issue, so probably a new BIOS will fix it. Not that it matters for me, after all the pain of this upgrade I'm even less enthusiastic about further upgrades. 3G is enough for what I want to do though, so I should be able to keep using the same hardware for at least another 5 years for that server. tbl: Thanks for the suggestion, it’s interesting to know how other Unix systems work with Xen. Generally I don’t have enough time to learn about the other distributions of Linux, let alone other Unix systems.

Stefano: My understanding of OpenVZ is that it’s like VServer in it’s design. This doesn’t work for some of the things I want to do as I want to run different kernel versions as DomU’s (or equivalent).

Jeff: Thanks, I should have tried that before upgrading to Unstable.

specialj: My laptop doesn’t get much travel nowadays, mostly it’s moved between desks and even when running Xen the batteries last the duration of the journey. But you are correct that it is a problem with Xen and a win for KVM.

Anon: I liked it when they had different names, Pentium 3, Pentium 4, Pentium D, and different clock speeds and cache sizes within that range. They stuffed it up a little by releasing both 32bit and 64bit chips under the name “Celeron D” and then abandoned it entirely in recent times.

geb: That sounds like a BIOS issue, so probably a new BIOS will fix it. Not that it matters for me, after all the pain of this upgrade I’m even less enthusiastic about further upgrades. 3G is enough for what I want to do though, so I should be able to keep using the same hardware for at least another 5 years for that server.

]]> By: geb http://etbe.coker.com.au/2008/05/02/the-future-of-xen/#comment-13454 geb Sat, 03 May 2008 07:15:23 +0000 http://etbe.coker.com.au/?p=578#comment-13454 even if the intel board is supposed to support 8GB ram, it breaks horribel. http://gebi.supersized.org/archives/2-Intel-965-board-with-8GB-Ram-and-Linux.html even if the intel board is supposed to support 8GB ram, it breaks horribel.
http://gebi.supersized.org/archives/2-Intel-965-board-with-8GB-Ram-and-Linux.html

]]> By: Anonymous http://etbe.coker.com.au/2008/05/02/the-future-of-xen/#comment-13453 Anonymous Sat, 03 May 2008 06:32:41 +0000 http://etbe.coker.com.au/?p=578#comment-13453 Go figure. People complained when Intel used and promoted processor speeds, and now they complain when Intel switches to an arbitrary performance/feature metric. Go figure. People complained when Intel used and promoted processor speeds, and now they complain when Intel switches to an arbitrary performance/feature metric.

]]> By: specialj http://etbe.coker.com.au/2008/05/02/the-future-of-xen/#comment-13441 specialj Fri, 02 May 2008 22:46:59 +0000 http://etbe.coker.com.au/?p=578#comment-13441 My current setup is to use Xen on servers and KVM on desktops (if the hardware support is present). For your Pentium-M laptop I'd think that VirtualBox might be the best solution since you have neither 64-bit support nor VT support, with the caveat that you may want to replace it with KVM should you ever upgrade. I can sympathize with your Xen problems. Right now all of my Ubuntu DomU's are unable to be upgraded from 7.10 to 8.04 due to a bug in the kernel that causes similar problems to what you mentioned. Perhaps it would shed some light on your issues: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/218126 However, it makes no sense to use Xen on a laptop due to Xen lacking power management facilities. If Xen ever gets CPU throttling support I would be quite happy, and perhaps if KVM can catch up in other areas it might be a reason to switch, even on the server (electricity is expensive). I haven't replicated tests recently but in the past I found KVM to be unsuitable for servers. For one thing it requires hardware virtualization support which not all of my servers have. Beyond that I found the scheduling to be sub-par. Xen is the only virtualization software I've used that fairly allocates resources. This can be tested by generating a high load in one domain and testing the responsiveness of the others. As with all software it's important to find the right tool for the right job and to keep your eyes on the other tools people are using. My current setup is to use Xen on servers and KVM on desktops (if the hardware support is present). For your Pentium-M laptop I’d think that VirtualBox might be the best solution since you have neither 64-bit support nor VT support, with the caveat that you may want to replace it with KVM should you ever upgrade.

I can sympathize with your Xen problems. Right now all of my Ubuntu DomU’s are unable to be upgraded from 7.10 to 8.04 due to a bug in the kernel that causes similar problems to what you mentioned. Perhaps it would shed some light on your issues:

https://bugs.launchpad.net/ubuntu/+source/linux/+bug/218126

However, it makes no sense to use Xen on a laptop due to Xen lacking power management facilities. If Xen ever gets CPU throttling support I would be quite happy, and perhaps if KVM can catch up in other areas it might be a reason to switch, even on the server (electricity is expensive). I haven’t replicated tests recently but in the past I found KVM to be unsuitable for servers. For one thing it requires hardware virtualization support which not all of my servers have. Beyond that I found the scheduling to be sub-par. Xen is the only virtualization software I’ve used that fairly allocates resources. This can be tested by generating a high load in one domain and testing the responsiveness of the others.

As with all software it’s important to find the right tool for the right job and to keep your eyes on the other tools people are using.

]]> By: Jeff Licquia http://etbe.coker.com.au/2008/05/02/the-future-of-xen/#comment-13439 Jeff Licquia Fri, 02 May 2008 21:10:43 +0000 http://etbe.coker.com.au/?p=578#comment-13439 FWIW, etch-backports has Xen 3.2. I'm currently struggling with qemu-dm, which doesn't seem to work at all, but from the sounds of it that's less of a concern for you. FWIW, etch-backports has Xen 3.2. I’m currently struggling with qemu-dm, which doesn’t seem to work at all, but from the sounds of it that’s less of a concern for you.

]]> By: Stefano http://etbe.coker.com.au/2008/05/02/the-future-of-xen/#comment-13427 Stefano Fri, 02 May 2008 16:23:48 +0000 http://etbe.coker.com.au/?p=578#comment-13427 Hi, nice article. I suggest you to try OpenVZ. It's a good compromise between Xen's flexibility and KVM speed. Hi, nice article.
I suggest you to try OpenVZ. It’s a good compromise between Xen’s flexibility and KVM speed.

]]> By: tbl http://etbe.coker.com.au/2008/05/02/the-future-of-xen/#comment-13423 tbl Fri, 02 May 2008 15:24:00 +0000 http://etbe.coker.com.au/?p=578#comment-13423 I have been using Xen since 2005. But instead of choosing Linux as Domain0, I choose NetBSD, one reason was pf, another that it was more easy to custom compile a kernel, and third reason networking was easier to understand and setup. I still use the same setup, running NetBSD and some Linux in DomU's. No problems, long uptime's. However Xen evolved and version 3 come, and I had version 2 running of Xen. NetBSD which is a small community, didn't have Xen 3 support, less PAE (now they begin to have). Beginning to feel the need to upgrade I begun to look for alternatives. Should I have to go back to Linux, messing with kernels and other things i didn' like? Then I catched the news (2006/2007) that Sun was working on integrating Xen into Opensolaris. I have since then been testing the functionality of Xen on Opensolaris. Xen on Opensolaris is a different, and more pleasing experience, a little bit like NetBSD, than Xen on Linux (which I also use). I get an intuitive feeling for networking and the interfaces. And things like Crossbow, which I run a beta release of just now (http://opensolaris.org/os/project/crossbow/CrossbowBeta/), makes it more interesting to run Xen (xVM) on Opensolaris. And nothing beats stability. Nvidia works out of the box ("accelerated graphics") 32/64 bit, Xen or no Xen (try that on Linux). And that's in the CrossbowBeta out of the box, together with the Zone functionality. And if Xen still feels ugly, VirtualBox may be a solution, also on Opensolaris (you have to download it). The box I'm running now, Amd64 asus a8v deluxe, no longer boots the default Linux kernel found in Ubuntu 8.04, because of changes in the Linux kernel (bye bye kvm testing). But why bother compiling another custom kernel, when Solaris boots, NetBSD boots? I want stability. I want Xen. And for that I need a stable system. And Xen need's a stable and mature operating system, with a stable kernel to run well. Therefore I welcome Opensolaris and the project "Indiana" which will be released this month. There I will continue to use Linux, Ubuntu 8.04, maybe Debian, NetBSD, and perhaps some Windows, in a stable environment of Opensolaris xVM. Not to mention also in the "package"; zfs, cifs, iscsi, vscan, dtrace ... all making virtualization and testing more easier. So perhaps try NetBSD or Opensolaris, or why not both? /tbl I have been using Xen since 2005. But instead of choosing Linux as Domain0, I choose NetBSD, one reason was pf, another that it was more easy to custom compile a kernel, and third reason networking was easier to understand and setup. I still use the same setup, running NetBSD and some Linux in DomU’s. No problems, long uptime’s.

However Xen evolved and version 3 come, and I had version 2 running of Xen. NetBSD which is a small community, didn’t have Xen 3 support, less PAE (now they begin to have). Beginning to feel the need to upgrade I begun to look for alternatives. Should I have to go back to Linux, messing with kernels and other things i didn’ like?

Then I catched the news (2006/2007) that Sun was working on integrating Xen into Opensolaris. I have since then been testing the functionality of Xen on Opensolaris. Xen on Opensolaris is a different, and more pleasing experience, a little bit like NetBSD, than Xen on Linux (which I also use). I get an intuitive feeling for networking and the interfaces. And things like Crossbow, which I run a beta release of just now (http://opensolaris.org/os/project/crossbow/CrossbowBeta/), makes it more interesting to run Xen (xVM) on Opensolaris. And nothing beats stability. Nvidia works out of the box (”accelerated graphics”) 32/64 bit, Xen or no Xen (try that on Linux). And that’s in the CrossbowBeta out of the box, together with the Zone functionality. And if Xen still feels ugly, VirtualBox may be a solution, also on Opensolaris (you have to download it).

The box I’m running now, Amd64 asus a8v deluxe, no longer boots the default Linux kernel found in Ubuntu 8.04, because of changes in the Linux kernel (bye bye kvm testing). But why bother compiling another custom kernel, when Solaris boots, NetBSD boots? I want stability. I want Xen. And for that I need a stable system. And Xen need’s a stable and mature operating system, with a stable kernel to run well. Therefore I welcome Opensolaris and the project “Indiana” which will be released this month. There I will continue to use Linux, Ubuntu 8.04, maybe Debian, NetBSD, and perhaps some Windows, in a stable environment of Opensolaris xVM.

Not to mention also in the “package”; zfs, cifs, iscsi, vscan, dtrace … all making virtualization and testing more easier.

So perhaps try NetBSD or Opensolaris, or why not both?

/tbl

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