Linux writing on mainframe wall for server clusters
Linux on the mainframe could spell the end for IA-based server clusters
IBM threw down the gauntlet last month with the launch of its Linux-only iSeries mainframe, which stirred both the operating system and high-end server market.
The iSeries not only pushes Linux into the enterprise arena, it also brings AS400/mainframe technology within reach of midrange networks. The combination could deal a severe blow to the long heralded architecture of distributed servers.
At the moment, Linux cannot handle all enterprise tasks, which is holding back a widespread switch from distributed servers to a single Linux mainframe environment. But the iSeries and Sun's recent Linux announcement have caused an avalanche of enterprise enthusiasm for Linux, which is likely to spark more applications and spur developers to tinker with the open-source code to make it deal with a greater variety of workloads.
In other words, the more widely accepted Linux becomes, the faster it will grow. In a way it is a little bit like Moore's Law except that it is application diversity rather than processing capacity that is doubling every 12 to 18 months.
Moore's Law was devised by Gordon Moore, co-founder of Intel. Last week the chip giant released a brief to reassure us that Moore's Law is still valid but now doubles over a longer timeframe.
In that case, the original version of the principle might apply better to Linux development. Ironically, it would be Intel which is most likely to suffer from this trend, if it indeed makes people move away from server clusters.
Once Linux matures enough to run most core business applications, there will be nothing to prevent network managers switching to an AS400 or mainframe environment.
There is little doubt that the likes of Sun, HP and Compaq will come up with an answer to the small mainframe threat. To replace maintenance-heavy server clusters, suppliers will bring out larger servers that use logical partitioning technology to create virtual servers.
But there is a catch that may make it very hard for servers to compete with mainframes in the long run. Analysts believe logical partitioning has its limits and can only consolidate some 32 servers effectively.
With the variety in web, file and email servers found on a modern network, many companies need to go beyond this limit. To consolidate hundreds of servers, you need the real thing: the virtual machine technology embedded in a mainframe architecture. Could it be that this old mainframe principle, which apart from a few enhancements has stayed the same for 30 years, proves stronger than the server philosophy?
It will be interesting to see if the combination of an old platform and modern application development will prove lethal, and turn server cluster technology into the dinosaur of the third millennium.