Original URL: https://www.theregister.com/2006/11/08/ibm_multicore/

One quad-core will do nicely

IBM ponders what users want and what they need

By Martin Banks

Posted in Channel, 8th November 2006 16:37 GMT

The race to be the first server vendor to announce systems running Intel's quad-core Clovertown processor may have been won by Dell but it is something of a pyrrhic victory. It is a racing certainty that most vendors in the x86 server market are likely making similar announcements in the very near future.

But while Intel and AMD race ahead on the technology front, at least one server vendor has started to ponder just what users will need, and what the practical limits of multi-core processors might be. Tim Dougherty, director of BladeCenter strategy with IBM has been pondering just such subjects.

In his view there is unlikely to be too much of a market for dual processor, quad-core servers, even though Dell is leading the pack in announcing just such a system. His reasoning is that, while quad core gives a well-documented power/performance advantage, there are likely to be issues with I/O access requirements in systems designs. So he sees a single quad-core processor as the sweet-spot server design for the immediate future. This would give the best balance between performance, I/O and applications capabilities.

In fact, he sees there being little need for multicore general purpose processors to grow beyond eight cores. At this point, it would start to move into the area of parallel processing, which is where IBM’s Cell processor technology will likely come to dominate.

Applications suitability is going to be more of an issue with quad-core processors, in that the real performance advantages will only come with those applications that have been written to fully exploit multi-threading capabilities. Indeed, with non-threaded applications Clovertown is likely to show worse performance than earlier Xeons.

Dougherty sees applications management and acceleration services being key technology requirements for the full exploitation of quad core processors, and this is expected to be incorporated in the virtualisation systems that are planned to be introduced with the X4 I/O management chip set.

IBM has had the X3 I/O chipset in place for some 18 months. This was designed to improve the I/O capabilities of servers using Intel processors – and particularly the then up-coming dual core devices - when set against AMD's HyperTransport. The X3 chipset, according to System X global brand manager Stuart McRae, is set to remain current until the first half of 2008 when it will be replaced by the X4 chipset. ®