Posted by Fraser Campbell
Fri, 27 Apr 2007 03:51:00 GMT
Kernel 2.6.21 was released yesterday, a few of the more interesting highlights:
- VMI now in default kernel (this is VMware’s layer on top of paravirt_ops), theoretically a fully paravirtualized Linux kernel on top of VMware might be do-able now
- updated KVM code which includes some paravirt_ops support and live migration
- clockevents and dynticks
The dynamic clock tick stuff is best covered over at LWN (see Clockevents and dyntick). This could have positive impact on power consumption and performance (particularly in virtualized environments). It will be interesting to see if certain virtual environments can now keep accurate time with a kernel such as this.
Posted in Kernel, VMware, KVM, Paravirtualization | no comments
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 in Xen, XenSource, VMware | no comments
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 in Xen, XenSource, QEMU, VMware, KVM | 2 comments
Posted by Fraser Campbell
Fri, 10 Nov 2006 03:31:00 GMT
Yesterday Red Hat offered a press release regarding virtualization in RHEL 5. Red Hat says:
“Customers care about open interoperability and certification for running joint Red Hat and VMware environments,” said Brian Stevens, CTO at Red Hat. “With this relationship, the two virtualization platforms that Red Hat Enterprise Linux will support are the VMware platform and the Red Hat Integrated Virtualization platform that will be available in Red Hat Enterprise Linux 5. The wide adoption of open source is a result of the commitment to interoperability. Support for our joint customers is just one more example of the efficacy of true open source development.”
Red Hat Integrated Virtualization platform means Xen of course, combined with Red Hat’s libvirt and virtualization manager.
The release further states that “Red Hat has already certified VMware Infrastructure as both a certified software application and a certified virtual hardware platform for Red Hat Enterprise Linux.”.
See full press release at http://www.redhat.com/about/news/prarchive/2006/vmware.html.
Posted in Xen, Redhat / Fedora, VMware | no comments
Posted by Fraser Campbell
Fri, 11 Aug 2006 13:02:00 GMT
Just noticed the site “Virtualization Gets Real” today from Ziff Davis Media. The site is dedicated to VMware technology from what I can tell. Their claim:
Welcome to “Virtualization Gets Real” – your online resource for information about server virtualization. Here you’ll find the Technology Briefs, eSeminars and other resources you’ll need to implement virtualization solutions the right way – from choosing the right partners to providing tools to help you integrate and manage your environment.
Check it out at http://www.virtualization.ziffdavis.com/.
Posted in Misc, VMware | no comments
Posted by Fraser Campbell
Thu, 20 Jul 2006 22:54:00 GMT
Today there were several presentations related to virtualization, first came Zachary Amsden presenting VMware’s VMI work.
Zach’s presentation was very technical and informative. Differences between traditional (full) virtualization and paravirtualization were discussed, some highly technical discussions followed and finally benchmarks were displayed.
Read more...
Posted in Xen, VMware | no comments
Posted by Fraser Campbell
Tue, 11 Jul 2006 15:15:00 GMT
Today ToutVirtual Inc announced the availability of VirtualIQ 525 as freeware.
VirtualIQ 525 includes monitoring, alerting and policy based automation for every VMWare product as well as the open-source Xen hypervisor.
The freeware version is available for up to 5 CPUs and 25 virtual machines, additional products are in the pipeline for this summer.
See full press release here.
Posted in Xen, Microsoft Virtual Server, ToutVirtual, VMware | no comments
Posted by Fraser Campbell
Fri, 21 Apr 2006 01:53:00 GMT
The Register weighed in today on the ongoing saga of getting paravirtualizationn officially supported in the mainline kernel:
A battle as to how Linux will handle future virtualization software from the likes of VMware and Xen has moved from a war of words to a war of indecision. The major parties involved – including Linux kernel maintainers – agree that a compromise over the virtualization interface must be reached, but no one seems to know exactly how to achieve this goal.
I have covered this topic briefly a few times in the past month, the register goes into quite a lot of detail and it’s well worth the read.
Read original article here.
Posted in Xen, Kernel, VMware | no comments | no trackbacks
Posted by Fraser Campbell
Sat, 15 Apr 2006 02:42:00 GMT
Stephen Shankland on CNet’s news.com wrote about the getting VMware’s VMI support into the kernel.
I blogged on this topic a few times in the past month in VMI – Progress Towards a Standard Paravirtualized API? and in Light at the end of the tunnel for kernel-xen?.
Shankland adds to this with some interesting quotes from kernel bigwig Andrew Morton and Xenmaster Ian Pratt.
This quote from Ian Pratt sounds promising:
The Open Source Development Labs has taken an active role in trying to clean up the situation, Pratt added. “OSDL has volunteered to set up meetings to get this stuff discussed,” he said, noting they would possibly be set up through a virtualization task force.
On the other hand:
Morton said the Xen programmers haven’t been active in the interface work. “This has been floating around for a year, and I’ve heard precious little from the Xen team on the topic,” Morton said.
There are a few other interesting statements in the article so you would be best to read it at source if interested.
Once again there is light at the end of the tunnel – I just can’t tell if it’s getting dimmer or brighter.
Posted in Xen, Kernel, VMware | no comments | no trackbacks
Posted by Fraser Campbell
Sat, 18 Mar 2006 01:42:00 GMT
There has been a lot of traffic on various linux kernel mailing list of late relating to virtualization. Much of the recent traffic is the result of a proposal and large patchset from VMWare (at least from Zachary Amsden of VMWare).
Zach has been posting periodically on linux-kernel since 1996 and judging by code and feedback he certainly knows his stuff. The latest from Zach is a plethora of patches that implement what VMWare is calling VMI or Paravirtualization API Version 2.0.
You can read the linux-kernel post here for a good overview of the work.
High level goals of the API are portability, high performance, maintainability and extensibility.
In the maintainability section the following statement is made:
To reduce the maintenance burden as much as possible, while still allowing the implementation to accommodate changes, the design provides a stable ABI with semantic invariants.
This statement is sure to raise the ire of kernel developers. More on that later.
Read more...
Posted in Misc, Kernel, VMware | no comments | no trackbacks
