Want to know what the future holds for VMware ESX, the server virtualization platform? Look no further than VMware Workstation 6, which completed its beta today and is now generally available.
As VMware's flagship product, Workstation has a long history debuting new ESX features, for example VirtualSMP. With millions of users worldwide (the product passed the 1 million user mark in 2002), VMware thinks of Workstation as "a massive proving ground for features that later end up in our server core," said James Phillips, senior director of software lifecycle solutions at VMware.
In particular, Phillips pointed to two experimental Workstation 6 features that have a place in future versions of ESX.
Record and replay
First shown on stage at VMworld to audience applause by VMware chief scientist Dr. Mendel Rosenblum, Workstation's new record and replay feature allows a developer to "record" the behavior of a virtual machine, including system behavior such as interrupts, and later "rewind" the VM and precisely "replay" its behavior.
"Think of it as a surveillance video" trained on a VM, Phillips said.
Phillips went on to say "software is completely deterministic – except if there are external events that interfere with execution." But because VMware inserts a virtualization layer between the VM and the rest of the environment, "we're in a position to completely capture everything that happens to the data."
Developers benefit from Workstation's record and replay in that they can more easily track down bugs in their code since they can easily reproduce problems and insulate their code from system-level variables. When replaying, developers can open up a debugger and step through the instructions one-by-one until they find the source of the trouble.
When record and replay makes its way in to VMware ESX, however, it will probably be used for entirely different purposes, for example high availability and security.
Imagine using record and replay for fault tolerance, Phillips said. "You take two servers and make one the master and start recording. Then when something goes wrong, you ship over as a set all the recorded operations [to the slave]," Phillips said. What that gives you, in effect, is "tandem-level fault tolerance" that, like other VMware products such as Distributed Resource Scheduling (DRS) "is really easy to implement."
As an experimental feature, VMware is not disclosing performance and storage overhead statistics for Record and Replay. However, Phillips said that performance overhead "is not out of control; anecdotally, I've heard 10%-ish, and we expect that number to come down."
Automatic paravirtualization with Virtual Machine Interface
VMware Workstation 6 is also the first virtualization platform -- from VMware or otherwise -- to support the Virtual Machine Interface (VMI) 3.0 paravirtualization interface, which Linux distributions based on the 2.6.21 kernel or higher support via paravirt_ops.
With VMI support enabled, the operating system communicates with the underlying virtualization platform and runs in paravirtualized mode, for better performance over the standard "full virtualization" offered by VMware.
Beyond performance, the benefit of VMI goes to operating system vendors, Phillips said. "No OS vendor wants to support everyone's hypervisor," he said. With a VMI-enabled hypervisor, an operating system can run paravirtualized or on native hardware, without requiring the OS vendor to support two separate, specialized OSes.
To date, the only VMI-compliant operating system is Linux Ubuntu Feisty Fawn. As other Linux distributions adopt newer versions of the Linux kernel, the range of Linux distributions that can run paravirtualized will increase. Furthermore, as an open standard, VMI is open for other vendors such as Sun Microsystems or Microsoft to implement as well.
IT admins new target audience
In the two years since VMware shipped Workstation 5, its user base has changed dramatically. According to a recent VMware survey, the majority of Workstation users are not developers, as one might expect, but IT administrators.
According to the survey, 58% of Workstation users identify as IT administrators, compared with just 25% who identify as developers. Even more surprising is that only 2% of Workstation users are in quality assurance (QA), compared with 13% that describe themselves as sales professionals that use Workstation for doing software demos.
"Workstation has been pigeonholed as this developer-centric tool, but the reality is that it's really desktop-centric," Phillips said. "The number of developers and test professionals using it is dramatically less than say, IT admins that want to test an application in a clean slate environment."
With those users in mind, VMware hopes to convince IT administrators to use another desktop-focused virtualization tool: VMware ACE (Assured Computing Environment). When users buy Workstation 6, they will receive a full license for the VMware ACE Option Pack, giving them the ability to author ACE desktops. Previously, authoring an ACE VM required the ACE Manager.
This offer does have a catch: It's only on for a limited time, and Phillips could not say how long it would last.
Workstation's other features
Brett Shavers is one of those non-developer Workstation users. As managing principal of the computer forensics firm NTI Associates in Bellevue, Wash., Shavers uses VMware Workstation to recreate desktop environments and data files on his computer for criminal, class action, and intellectual property lawsuits. A Workstation user for three years, Shavers' favorite new feature in Workstation 6 is support for faster USB 2.0.
When working, "we copy the original evidence to an external USB hard drive," Shavers explained. USB 1.0 was simply, "really slow."
Shavers also uses Workstation at home, for personal use. "My desktop gets kind of cluttered, so I like to browse the Internet in a VM, and do my downloads there. Then I can test it out to make sure there aren't any problems," he explained. Shavers also has his kids go online from within a VM to avoid viruses and spyware.
Other features of VMware Workstation 6 include better performance, support for Microsoft Vista hosts and guests, integrated physical-to-virtual (P2V) capabilities, background virtual machine execution, APIs to automate the testing of virtual machines, and support for multiple monitors.
Last but not least, Workstation 6 does hold some features that only a developer could love: integration with two of the leading integrated development environments, Eclipse and Microsoft Visual Studio.
Pricing for VMware Workstation 6 remains unchanged at $189 for a downloaded copy, or $209 with manuals and media.
Let us know what you think about the story; email: Alex Barrett, News Director.