Disk drives

Most people don't get too excited about disk drives because constant increases in capacity have meant that disks rarely fill up. But there's more to a disk than its size, and the recent launch of Intel's X25-M solid state drive (SSD) suggests that disks for 2009 and beyond could be very different to those in common use today.

Although the X25-M is not the world's first SSD, the new technology needs the intervention of a giant like Intel to jump-start interest. SSDs have undeniable benefits compared to magnetic disks. Firstly, they're fast. The X25-M offers a sustained data transfer rate of 250MB/s for reads and about a third of this for writes.

Secondly, as SSDs have no moving parts, we can reasonably expect the term 'disk crash' to be consigned to the history books. On the downside, the X25-M isn't cheap and its capacity isn't huge (80GB or 160GB), but – as with all new technologies – it's likely that improvements will come thick and fast. We hope 2009 is the year of the SSD.

Moore's Law continues

Few manufacturers were prepared to reveal their plans for the more distant future, but this didn't prevent us from engaging in a bit of long-range crystal ball gazing – with a little help from the history books. For example, the history of semiconductor development has been characterised by various trends. Surely the most famous is Moore's Law, which states that the number of transistors that can be crammed onto a chip doubles every two years.

This law has held true since 1965, and today's largest chip – the Intel quad-core processor codenamed Tukwila – has in excess of two billion transistors. Trends do run out of steam though; perhaps the most famous fad to do so was that for clockspeed increases.

This will surely be the fate of Moore's Law one day, but the good news is that most experts expect that we will see Moore's Law continue until at least 2022. This means that it's possible that we will see chips with four billion transistors in 2010, eight billion in 2012 and so on up to a staggering 256 billion in 2022.

If the predictions prove true and we do see this number of transistors, how will they be employed? Will it just be more of the same?

The next big challenge

For an independent view of the answer to this question, we spoke to Rudy Lauwereins, Vice President of Embedded Systems Designs at IMEC, Europe's largest independent research centre in nanotechnology and nanoelectronics. "It would be the same," said Lauwereins, "if you assume that the architecture isn't going to change. But a few things give me the feeling that we'll see a drastic change in architecture."

Lauwereins put the current trends into context by taking us through the evolution of processors from the 4004 to the present day. Initially, the increase in transistor count was used to boost the core computing infrastructure.

This meant that the register width increased, as did the number and complexity of the instructions. Because this change occurred in parallel with increasing clockspeeds, problems occurred because the speed of memory struggled to keep up. The industry then entered a phase where extra transistors were used to get data to the processing engine.

The next step concerned the problems caused by increasing power consumption. This caused a halt to increases in clockspeed and required transistors to be spent on power management. The most significant change at this point was the migration to multiple cores. Much of this will be familiar to anyone who has followed the development of processors, and each of these trends is evident in the new Core i7. But Lauwereins' suggestion of how transistors will be used in the future was vastly different to what we've seen historically.