How Windows 7 will -- and won't -- work better with SSDs

Computerworld - The first generation of solid-state drives (SSD) introduced in PCs last year failed to live up to the hype.

Though praised for using less power and generating less heat than conventional hard disk drives, SSDs weren't as fast as promised. Their capacity and longevity, especially with low-end models found in netbooks, left a lot to be desired.

Much of that was because of the poor quality of the SSDs themselves. But another problem was that neither the hardware nor the software had caught up to SSDs.

"Operating systems need to treat SSDs differently than hard drives," said Don Barnetson, senior director of marketing for SSDs at SanDisk Corp.

At its Windows Hardware Engineering Conference (WinHEC) in Los Angeles this week, Microsoft Corp. promised that the upcoming Windows 7 would work better with SSDs, though SSD makers and PC makers will need to do their part, too.

Peter Glaskowsky, an analyst at The Envisioneering Group, said it's good that Microsoft is stepping up, rather than relying on SSD vendors such as Samsung Electronics Co., SanDisk and Intel Corp. to do all the heavy lifting.

But he and other experts say unless Microsoft takes one more giant step, Windows 7 will boost SSD performance in only an incremental way.

"Microsoft could make Windows 7 a much more flash-memory-aware OS. But you would need to change the [drive] interface," he said. "That's not being contemplated within the scope of Windows 7 today."

That leaves a potental opening for Apple Inc. or even a Linux netbook PC maker.

Optimizing SSDs for Windows 7 is key. Sales of laptops, especially netbooks, are on the rise. Meanwhile, SSD prices are plummeting and capacities and quality are growing. According to Gartner Inc. data shared by Microsoft, a 512GB SSD that costs almost $600 today should be less than $300 by 2010, when Windows 7 is expected to be officially released.

"SSDs are on the path to reach their full potential," Microsoft senior program manager Frank Shu said.

In a WinHEC presentation, Shu outlined four ways in which Windows 7 is expected to improve upon Vista and XP support for SSDs.

First, Windows 7 will turn off disk defragmentation when it detects an SSD instead of a spinning disk drive.

Defragging disks speeds up the reading of data from conventional hard drives by moving similar data together. But flash-based SSDs are already fast at reading data. Instead, SSDs are slow at writing data. Moreover, the process of erasing and moving data requires "flashing" the memory cells with high voltage. That gradually wears out the SSD.

Defragmentation thus shortens an SSD's lifespan without improving performance, Shu said.