Andrew Binstock

As virtualization continues its fast run at transforming IT, many organizations are starting to employ the technology to create and manage transiently configured systems. These systems are typically assembled for a one-off project and torn down at project end. Virtualization is an almost perfect match for this need. IT organizations that employ virtualization for temporary systems rely on software packages called virtual lab managers, or just lab managers for short.

The term "lab managers" doesn't quite describe all of the purposes these solutions are good for. The use cases for temporary virtualized systems cover a wide spectrum, including development, testing software, reviewing new products, running demos, doing in-house instruction, and so on. Lab managers simplify buildup and teardown, while providing many other services whose needs are not easily anticipated until you deploy virtual machines this way on a regular basis.

Artwork: Chip TaylorMicrosoft's Windows 7 operating system is receiving raves in its pre-release testing. While much of the kernel that lies at the heart of the operating system is based on Vista code, several key advances have been made that get rid of Vista annoyances and greatly improve the user experience. Inside the kernel, one important change centers on how multithreaded applications are run. The threading advances provide benefits in energy reduction, scalability, and, in theory, performance.

To check out the benefits on the desktop, I ran tests that reflect the most common use case for heavily threaded desktop apps -- namely, graphics-oriented software. Programs such as Adobe Photoshop and other graphical applications query a system's capabilities at startup and self-configure workloads accordingly. They typically use all the processor cores and as much RAM as they can get away with monopolizing. This approach enables them to provide the fastest performance. So I checked how such programs perform using the Viewperf benchmark (an omnibus graphics benchmark from SPEC, the Standard Performance Evaluation Corporation) and Cinebench, which is a pure rendering benchmark from Maxon Computer. Both benchmarks follow InfoWorld's tradition of using benchmarks that you can download and run on your own systems to see how your mileage varies. Both benchmarks can be obtained at no cost.

Long-life batteries from Dell and HP can keep laptops running for as many as 20 hours at a stretch. But you don't need a powerful external battery to get more use out of your current battery. There are several things you can do now to extract precious additional minutes from the basic six-cell battery found in most laptops.

Adjust only a few factors and you'll derive most of the available power savings. The biggest consumers of battery power are the screen, the processor, the optical drive, and the disk. Of these, the screen is by far the most important. It's also the easiest to adjust. Lower the brightness of the screen to the lowest level at which you can comfortably work and you'll have done more to save battery life than any other tweak can deliver.

The agile revolution that began in software development in the 1990s has been inexorably making its way into mainstream IT organizations. Today, one of the most adopted agile practices is unit testing, where developers write hundreds of small tests for exercising their own code. Although the benefits of unit testing are widely recognized, there's growing evidence that unit testing might have reached its high-water mark and be entering a period of stagnation or even decline.

Signs that unit testing has hit a wall include the high-profile collapse of Agitar, which was known widely for a good, if expensive unit-testing product. CEO Jerry Rudisin told the SD Times that Agitar's collapse (it was bought by McCabe Software in June was due simply to the fact that "unit testing hasn't taken off as a mainstream practice." Joe Ponczak, who heads up Condign Software, the makers of automated unit test generation tools and metrics dashboards, says he believes the Agitar failure was brought on by slower-than-desired growth, "not at the level expected from a Silicon Valley startup."

Andrew Glover, president of the agile-development consulting firm Stelligent, blamed Agitar's high price. "Only very large enterprises could afford it. And it was hard to justify paying those prices for a product that simply automated what developers could already do for themselves with free tools," he says.

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Why Unit Testing May Be Losing Its Allure

Of course, Agitar is just one company, and its experience is hard to translate as an overall trend -- especially because the major tools used in unit testing are available as free open source, such as JUnit and TestNG for Java and the xUnit frameworks for other languages, as well as the free code-coverage tools Cobertura and Emma. Most of the commercial products focus on automatic generation of unit tests and coverage analysis.

But consider the typical experience of Stelligent's Glover when he consults on development approaches with clients: "When I go into sites, I would love to turn them on to the benefits of the TestNG test framework," he says, "but most organizations do so little unit testing, if any, that I stick with the simple, well-known xUnit tools, so as not to create confusion. Most organizations are just not ready to learn anything more than basic unit testing -- if that."

While languages such as Python and Ruby have active unit-testing cultures, there are signs that, in the Java community at least, resistance has built up against the unit testing idea. I posted the question on unit testing's future in my blog recently, and got several hundred responses. Among those, I identified two major threads of concerns.

One issue is that unit testing seems to offer little value. "The problem with unit testing is that it increases the cost of development before you know whether what you developed is what you needed. Afterwards when you have a working solution, there's little interest in writing unit tests as what you have works, and your management wants you to move on," wrPeterB.ote one anonymous poster. "Many developers and managers mistakenly think that by cutting testing, they well get feature X out faster. What they don't realize is that you are robbing Peter to pay Paul," wrote Peter B.

The other issue was annoyance over evangelism, which is at the core of much of the agile movement (which began with a signed manifesto and a formulated creed). "Please, please, please, no more evangelism!!" wrote Gabriel C. A segment of the agile development community has adopted unit testing in a radical way, insisting that tests be written before the code.

This approach, called test-driven development, is intended to clarify design before committing to code. Its proponents have been zealous in promoting test-driven development as the best way to program, but for many developers that evangelism has become so overbearing that it makes unit testing as a whole unappealing.