Feeds

Linux team tells VMware and Xen to get their acts together

Play nice and have a chat

Internet Security Threat Report 2014

The wait debate

The two camps have debated VMI for months on Linux kernel mailing lists, with other developers from IBM, Red Hat, Oracle and elsewhere chiming in.

"Most of our interactions have been on that level," VMware senior director of research and development Jack Lo said.

VMware has reached out to the OSDL (Open Source Development Labs) and other unnamed parties to help set up a public forum for discussing the interface issue with Xen backers and anyone else who wants to show up.

But, after interviewing a number of people for this story, we get the sense that such a meeting is a concept at best right now. The parties involved proved reticent to nail down a time when they actually plan to sit down and don't seem all that determined to approach a debate until all the behind-the-scenes political posturing has taken place.

VMware has received praise for being so open with VMI and encouraging debate on the kernel mailing lists that include Xen backers. In addition, VMware has helped itself by setting up a slick VMI website that displays votes of support from the likes of IBM, HP and Novell.

The Xen camp, by contrast, has been criticized for taking the interface issue for granted and assuming its technology would go into Linux.

"This will take more work than the Xen people are anticipating," Morton said.

One Xen backer said a disconnect occurred where the Xen camp thought SuSE and Red Hat would use their close ties with the Linux kernel maintainers to sell the Xen interface. "As it turns out, that was a mistake. Morton wants more contact from us," he said.

On the mailings lists and in discussions, Xen advocates say VMware's VMI simply will not allow for the performance levels they would like to see out of virtualizaton. Xen, which already relies on the paravirtulization model, has learned a myriad of lessons about how a paravirtualized API should operate - skills that those like VMware and Microsoft that are just making their way toward paravirtualization have yet to acquire, Xen backers say.

In particular, they argue that VMI will not support I/O virtualization or SMPs.

VMware responded in a statement saying, "the VMI patches that we recently sent to the Linux kernel mailing list do include SMP support. I/O virtualization isn't in the spec today - it's an area of future work, and we're looking to collaborate with people on it."

More broadly, some Xen backers argue that VMI is simply a "crippled software version" of the virtualization hardware tools AMD and Intel have started building into their chips to make running virtual operating systems easier. That would make VMI rather redundant. Other VMI critiques include a proliferation of kernel hook points, a design that can't support optimizations Xen backers have found to be critical for top performance and weak semantics.

VMware counters by saying its approach requires less kernel changes than Xen, while delivering solid performance.

There are, in fact, laundry lists of other disputes - down to simple issues such as the interface name - that will have to be worked out.

Our sense is that VMware is honest about wanting an open interface but part of its openness stems from a desire to thwart Xen's apparent Linux edge. Xen 3.0 will be bundled with upcoming versions of Red Hat and SuSE, and Xen has a virtualization protocol license from Microsoft. VMware can't claim victories on either of those fronts and, as the clear market leader, is being pigeonholed to a degree by rivals. An open VMI interface could keep it closer to the Linux camp.

Xen, by contrast, wants to make the most of its open source ties and create the tightest possible bonds with Linux. Behind closed doors, some Xen backers say that Sun, Microsoft and Novell will refuse to support VMI. Such political manoeuvering shows how seriously Xen backers take this debate.

It's in Linux customers' best interests that all of this get worked out as soon as possible. The worst scenario would require ISVs and customers to certify applications for a host of paravirtualization interfaces.

As you can tell, however, it seems pretty unlikely that either VMware or Xen advocates will reach an agreement anytime soon, despite their promises to do so. And you can image how exciting the battle will become should the likes of Microsoft, IBM, SWsoft and others decide they want in on the issue as well. Yes, that's right. Microsoft may be a key player in a Linux kernel squabble.

You can expect more and more of these kinds of debates in the coming years, as server virtualization hots up even more. Microsoft, the open source player Xen and the proprietary middleman with all the market share VMware. Can you ask for anything more? ®

Beginner's guide to SSL certificates

More from The Register

next story
Docker's app containers are coming to Windows Server, says Microsoft
MS chases app deployment speeds already enjoyed by Linux devs
'Hmm, why CAN'T I run a water pipe through that rack of media servers?'
Leaving Las Vegas for Armenia kludging and Dubai dune bashing
'Urika': Cray unveils new 1,500-core big data crunching monster
6TB of DRAM, 38TB of SSD flash and 120TB of disk storage
Facebook slurps 'paste sites' for STOLEN passwords, sprinkles on hash and salt
Zuck's ad empire DOESN'T see details in plain text. Phew!
SDI wars: WTF is software defined infrastructure?
This time we play for ALL the marbles
Windows 10: Forget Cloudobile, put Security and Privacy First
But - dammit - It would be insane to say 'don't collect, because NSA'
Oracle hires former SAP exec for cloudy push
'We know Larry said cloud was gibberish, and insane, and idiotic, but...'
Symantec backs out of Backup Exec: Plans to can appliance in Jan
Will still provide support to existing customers
prev story

Whitepapers

Forging a new future with identity relationship management
Learn about ForgeRock's next generation IRM platform and how it is designed to empower CEOS's and enterprises to engage with consumers.
Why cloud backup?
Combining the latest advancements in disk-based backup with secure, integrated, cloud technologies offer organizations fast and assured recovery of their critical enterprise data.
Win a year’s supply of chocolate
There is no techie angle to this competition so we're not going to pretend there is, but everyone loves chocolate so who cares.
High Performance for All
While HPC is not new, it has traditionally been seen as a specialist area – is it now geared up to meet more mainstream requirements?
Intelligent flash storage arrays
Tegile Intelligent Storage Arrays with IntelliFlash helps IT boost storage utilization and effciency while delivering unmatched storage savings and performance.