The incredible shrinking operating system

From the software concept called JeOS (pronounced “juice”), the Just Enough OS, to hardware concepts like Celio RedFly, an 8-inch screen and keyboard device running applications off a smartphone via a USB or a Bluetooth connection, there are an increasing number of indications that the center of gravity is shifting away from the traditional massive operating systems of the past.

Even the major OS vendors themselves are saying that the next versions of their OS — Windows 7, Linux in its many distributions, and Mac OS X 10.6, aka Snow Leopard — are getting a smaller footprint.

There are many reasons for the traditional OS to shrink and for new OSes to start small, but two stand out:

One, a smaller code base is easier to manage and secure than a large one. For example, estimates for Vista's development costs run around $6 billion, and BusinessWeek has estimated that 10,000 employees spent about five years developing it.

Two, a smaller OS can run on a greater variety of devices, and as netbooks, smartphones, and new devices such as the iPod Touch gain traction, the benefit of a smaller OS becomes hard to ignore. Today, Microsoft's Windows Mobile is a separate code base from the desktop Windows, while Apple's iPhone OS is a both a subset of and extension of the Mac OS. In both cases, that adds a lot of work for their companies and for application developers. And it means that customers must support an unwieldy number of operating systems.

What Microsoft, Apple, and the Linux community are up to

“Ideally, we want to see Windows 7 run across a spectrum of hardware: small, standard, or desktop,” says James DeBragga, general manager of Windows Consumer Marketing at Microsoft. Apple hasn't said why it wants Mac OS X to use fewer resources, but a common theory is that it wants future iPhones and perhaps netbook or tablet devices to run the same OS as its beefier Macs do.

DeBragga told InfoWorld that Microsoft designed Windows 7 to reduce the overall memory footprint compared with Windows Vista. It did so by reducing the overall number of services running at boot, improving Desktop Windows Manager memory consumption and reducing the memory requirements for features throughout Windows 7. “Users have no patience for a long boot-up or shut-down time,” says Dan Kusnetzky, an independent research analyst.

Linux distribution vendors are also slimming down their versions of Linux. Ubuntu, for example, has stripped out MySQL, CUPS (Common Unix Printing Service), e-mail, and LDAP functionality to bring the size of its OS down from about 700MB to 200MB.

And Red Hat, Novell, and Ubuntu have all delivered stripped-down versions of their Linux distros for use in virtual appliances, several of which often run on one physical computer, so footprint becomes a key issue for them. Red Hat's AOS (Application Operating System), for example, lets you run Linux Enterprise Edition apps unmodified in a portable virtual machine. And JeOS — which Ubuntu, Novell, and others offer — builds a stack that is “just enough” to support that application by analyzing what APIs and library components need to be called for what functions.

While Apple always plays it close to the vest, it too has stated publicly that the next Mac OS will be smaller: “Taking a break from adding new features, Snow Leopard … dramatically reduces the footprint of Mac OS X, making it even more efficient for users and giving them back valuable hard drive.”

Not everyone is convinced that the traditional OSes will stay small. Tony Meadow, president of Bear River Associates, says that the current OS footprint reductions are all about pruning, such as removing old graphics APIs. But he believes that new capabilities will pull the OSes to keep growing, despite the periodic pruning.

Beyond making the OSes smaller for physical computers and virtual machines, the major platform providers face a new pressure to reduce their OSes' size: the several new classes of devices, from netbooks to smartphones. Netbooks are a good example: Because their hardware resources are much more limited than regular laptops', Microsoft has had to keep Windows XP available for them, since Vista simply can't run on them.

Much of the latest mobile hardware can be run to good advantage on microprocessors and OSes that require less power. The high-tech rumor mill lately has been abuzz about the possibility of a full-size notebook running a smartphone-oriented processor such as ARM's with an embedded version of Linux; such a device would have a battery life of days, not hours. “To an ARM device, a laptop looks like the Hoover Dam in terms of battery life,” says Jim Ready, CTO of MontaVista Software.

Dell has already taken a step in this direction with its “BlackTop” Latitude laptop, which can boot into Linux for e-mail, Web access, and document viewing instead of Windows (which you can also boot into for traditional work).

Smartphones such as the Apple iPhone and the Research in Motion BlackBerry are also increasingly providing computerlike capabilities, creating demand for computerlike OSes to run on them. Witness Celio's RedFly, a smartphone terminal that connects to a cellular phone over Bluetooth or a USB. It weighs just 1.4 pounds and features an 8-inch screen and an 8.3-inch keyboard large enough to do real work. RedFly uses the Windows Mobile OS as an operating system, and its users typically work in their browser, often using Web 2.0 applications.

The dependence on the browser, instead of the OS, in such devices has convinced some that the OS should shrink even further, ceding much of its role to the browser.

One of those believers is Philippe Winthrop, a mobile analyst at Strategy Analytics. He says the notion of cloud computing is a major driver behind the movement away from full-featured OSes and toward having critical functions reside in the browser.

For example, the SDK for the hot new Palm OS provides developers with CSS, JavaScript, and XML, all the tools that are used in a modern browser. These tools let developers write applications as widgets that do not require the support of an onboard OS.

Winthrop also says when back-end and front-end services both use the same Web technologies, the need for a powerful OS is reduced.

Tomi Rauste, president of Movial Creative Technologies, a mobile consultancy, picks up on that idea. Rauste believes combining Web technologies obviates the need for application integration at a deeper level. “Using Web technologies to customize a user interface is far easier than using interface technologies where you have to have native coding skills to change the interface,” Rauste says.

Of course, Microsoft is not convinced that the browser will take over much of the OS. While there are a number of embedded versions of Windows, including Windows CE and Windows XP Embedded, where hardware designers use only those components needed for their device, DeBragga says he doesn't see the browser taking over most of operating system chores.

It is true that 50 percent of the time a user is in his or her browser, but the browser is not suited to handle the other applications a computer can handle, DeBragga argues. He cites document editing and video editing as example tasks that don't require a browser but do require a powerful operating system.

Bear River's Meadow agrees. While the OS may get smaller and more users will live in their browsers, he says there is still a lot of competitive advantage to having a fully featured OS that does things other operating systems don't. Case in point: “OS X running on the iPhone gives the iPhone incredible power.”

But even that legitimate OS dependence is changing, counters Winthrop. He points to Photoshop.com and Photoshop Express, Web versions of the premier photo-editing package Adobe Photoshop. There was a time when no one would have thought that feature-rich Photoshop would ever be a Web 2.0 application, but to a great extent it is now.

For a growing class of users, notes independent analyst Kusnetzky, a device that presents a Web browser, Internet mail, a word processor, and a calendar is more than sufficient for their needs.

It's certain the OS will continue to shrink, in whatever direction

The incredible shrinking of Windows 7, Mac OS X Snow Leopard, and Linux JeOS are no accidents. The OS center of gravity is indeed shifting away from the large do-it-all operating systems to a far more targeted approach.

The reason for these changes by the major vendors is downright Darwinian. All of them realize that they must adapt or die as virtualization, cloud computing, the explosion of unique devices, and the desire for more efficient, less costly operating systems all drive the next generation of business users toward smaller, less costly, and more efficient operating environments.