Posted by Fraser Campbell Tue, 04 Sep 2007 02:37:00 GMT
Recently appearing on Google Code is the Ganeti project.
Ganeti “is a virtual server management software tool built on top of Xen virtual machine monitor and other Open Source software”.
Ganeti supports 1-25 physical nodes, and HA using DRBD. It is interesting to see something based on DRBD, I had never considered it for production use but perhaps my reservations are unfounded.
Posted by Fraser Campbell Sun, 01 Jul 2007 15:31:00 GMT
Mickael Bailly has created a 5 part tutorial regarding his virtualization setup using RHEL5, Xen and GFS. It will be an interesting read for anyone who hasn’t used or studied Red Hat’s recent Xen release:
Enjoy.
Update: Unfortunately this presentation is offline. If anyone knows of an alternate location let me know, since I don’t host it I don’t control whether it’s available or not.
Posted by Fraser Campbell Wed, 02 May 2007 12:09:00 GMT
It looks like RHEL4 Update 5 is now out in some form. I didn’t see any official announcement yet but last night my internal yum repository got updated with a pile of RPMs which got me curious.
Anyway, whether Update 5 is official or not you can now grab an official Xen domU kernel for RHEL4 right from Red Hat.
Kernel errata package document is RHBA-2007-0304. You can grab either kernel-xenU-2.6.9-55.EL.i686.rpm or kernel-xenU-2.6.9-55.EL.x86_64.rpm.
Update: Red Hat’s release notes are here.
Posted by Fraser Campbell Wed, 02 May 2007 10:54:00 GMT
Tucows Email Service is a large scale hosted email service and there is a new release in the works that is almost ready to be unleashed on the public (well at least the resellers).
In a recent blog post Tucows has let it slip that the new architecture is based on Sun X4600 servers running Xen virtual machines.
See Tucows Email Service: What’s Under the Hood? for the details – it is nice to hear about Xen getting some large production workloads.
Posted by Fraser Campbell Sun, 29 Apr 2007 16:02:00 GMT
Papers from the recently held Xen summit are now available online at http://xen.xensource.com/xensummit/xensummit_spring_2007.html.
With roughly 30 presentations online it’s a little tough to summarize, if you’re interested in Xen check it out.
FYI, it appears likely that support for paravirtualized Linux on Xen might finally make it into the next kernel (2.6.22), I won’t be holding my breath but things are finally sounding promising.
Posted by Fraser Campbell Thu, 08 Mar 2007 23:56:00 GMT
VMware published a A Performance Comparison of Hypervisors at the end of January. Since the paper only discusses Windows I didn’t bother commenting – I don’t give two hoots about Windows.
Still the story is becoming amusing enough to warrant some study. Simon Crosby, Xensource CTO, recently published his thoughts the study:
All of XenSource’s commercial products match or beat ESX performance for Windows in all but a couple of benchmarks. This for a new product, and using the HVM feature set that has never been tuned. For Linux, we absolutely thrash ESX, which should come as no surprise. We’ll publish all of our results… just as soon as we get permission from VMware, that is.
Simon’s complete commentary is available in the Xensource blog here.
I would really have to agree with Simon, there are various commercial implementations of Xen (even if they aren’t allowed to be called that) and all will undoubtedly perform better than the older open source codebase that VMware did their comparison against.
Since VMware is comparing apples to oranges it reminds me a bit of the benchmarks I did a year ago with SuSE on Xen versus SuSE on ESX. Let’s just say embarrassing is not the word, joke might be the word but it sounds rather unprofessional – paravirtualization does help whether it’s just a paravirtualized network driver as in VMware’s windows benchmarks, or if it’s a completely paravirtualized kernel as in my SuSE on Xen tests.
Let’s hope that this evil policy of banning free and open benchmarking is lifted so that reasonable public discourse can take place without threat of lawsuit.
Posted by Fraser Campbell Sat, 03 Mar 2007 05:38:00 GMT
This week Red Hat made available a BETA of their 5th update to RHEL 4 (we would call it RHEL 4.5).
Most noteable in this release is that Red Hat now includes a kernel that can run paravirtualized on top of Xen.
This will mean that Red Hat shops can jump on paravirtualized Xen virtual machines with relative ease, and quite soon. RHEL 5 can be used for the base of the Xen virtualization solution but all of those virtual machines that your developers use can stick with the tried and true RHEL 4.
Thanks to internetnews.com for the news. See their article for more details.
Posted by Fraser Campbell Wed, 28 Feb 2007 02:52:00 GMT
For those who missed it (like me) Enomalism 0.6.3 was released on Feb 22nd. Additions are:
Go check it out on the sourceforge page or at http://www.enomalism.com/.
Posted by Fraser Campbell Tue, 27 Feb 2007 13:05:00 GMT
Ulrich Drepper is lead maintainer of the Linux C library (GNU libc), works for Red Hat and is well known in Linux circles – basically he is one smart cookie.
Last night he has posted a great article entitled Xensource/VMWare start sandbagging.
The article discusses the fact that Linux already has great support for NUMA, SMP, scheduling, hardware drivers, etc. My favorite “As for better scheduling with a hypervisor: that can only be a joke.”.
We can expect the marketing machines to crank out reams of verbage in the next 6 months but I trust Mr. Drepper more than I would trust anything I see coming from the corporate presses.
Linux as the hypervisor just makes sense. Jeff Dike has been pushing the idea for years with UML and UML continues to move forward.
The only slight beef (or question) I have with KVM is why has it diverged from QEMU? More specifically KVM relies on QEMU for it’s device emulation but it also requires hardware virtualization. Now that QEMU’s kernel accelerator is open source could KVM and QEMU not be merged back together to give us one high performing solution that would support both VT and non-VT capable hardware?
Posted by Fraser Campbell Mon, 26 Feb 2007 20:45:00 GMT
news.com has a very good article about KVM. It discusses plans of some of the major Linux distributors as well as some of the social issues around why KVM is rapidly gaining acceptance while Xen is still fighting for it (within the kernel community).
See KVM steals virtualization spotlight. for full story.
