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Tilera To Release 100-Core Processor
angry tapir writes "Tilera has announced new general-purpose CPUs, including a 100-core chip. The two-year-old startup's Tile-GX series of chips are targeted at servers and appliances that execute Web-related functions such as indexing, Web search and video search. The Gx100 100-core chip will draw close to 55 watts of power at maximum performance."
Wikipedia claims it's a MIPS-derived VLIW instruction set.
Mark Kretschmann - Amarok Developer, KDE Member
Unfortunately these days the meaning of supercomputer gets a bit diluted by many people calling clusters "supercomputers". They aren't really. As you noted what makes a supercomputer "super" isn't the number of processors, it is the rest, in particular the interconnects. Were this not the case, you could simply use cheaper clusters.
So why does it matter? Well, certain kinds of problems can't be solved by a cluster, just as certain ones can. To help understand how that might work, take something more people are familiar with like the difference between a cluster and just a bunch of computers on the Internet.
Some problems are extremely bandwidth non-intensive. They don't need no inter-node communication, and very little communication with the head node. A good example would be the Mersenne Prime Search, or Distributed.net. The problem is extremely small, the structure of the program is larger than the data itself. All the head node has to do is hand out ranges for clients to work on, and the clients only need to report the results, affirmative or negative. As such, it is something suited to work over the Internet. The nodes can be low bandwidth, they can drop out of communication for periods of time and it all works fine. Running on a cluster would gain you no speed over the same group of computers on modems.
However the same is not true for video rendering. You have a series of movie files you wish to composite in to a final production, with effects and so on. This sort of work is suited to a cluster. While the nodes can work independent, the work of one node doesn't depend on the others, they do require a lot of communication with the head node. The problem is very large, the video data can be terabytes. The result is also not small. So you can do it on many computers, but the bandwidth needs to be pretty high, with low latency. Gigabit Ethernet is likely what you are looking at. Trying to do it over the Internet, even broadband, would waste more time in data transfer than you'd gain in processing. You need a cluster.
Ok well supercomputers are the next level of that. What happens when you have a problem where you DO have a lot of inter-node communication? The result of the calculations on one node are influenced by the results on all others. This happens in things like physics simulations. In this case, a cluster can't handle it. You can slam your bandwidth but worse, you have too much latency. You spend all your time waiting on data, and thus computation speed isn't any faster.
For that, you need a supercomputer. You need something where nodes can directly access the memory of other nodes. It isn't quite as fast as local memory access, but nearly. Basically you want them to play like they are all the same physical system.
That's what separates a true supercomputer for a big cluster. You can have lots of CPUs and that's wonderful, there are a lot of problems you can solve on that. However that isn't a supercomputer unless the communication between nodes is there.