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New SGI Altix 3000
dlloyd writes "SGI has just publicly announced the Altix 3000 series of computers that can scale from 4 to hundreds of processors, with up to 64 processors per single system image. Processors each come in a C brick that has 4 CPUs. I/O is done though IX and PX bricks (12 PCI slots per brick, IX bricks have a base I/O controler and two ultra 160 disks inside), just like on the Origin 3900 series. Anything more than 8 CPUs (2 C bricks) is connected by R bricks, which route the NumaLink packets between nodes. The NumaLink network is good for an aggregate 6.4 gigabytes/sec to *each* node. That scales as you add more C and R bricks. Basically, you can think of this as SGI's origin 3000 series, except that it runs Linux and has Itanium2 processors. The performance and scalability is like nothing that has ever run Linux and is *far* ahead of the competition. For those of you who wonder why anyone would need a 64 processor Linux machine, many scientific and technical customers prefer running their code on large, single system image machines. Large single system image machines are also less labor intensive to maintain and admin, plus they work much better on code that needs to share memory and pass messages between threads (even myrinet and mpi is glacial compared to the SGI numalink network and running code multithreaded)."
Yeah, you're wrong. This isn't a beowulf, it's a multiprocessor box. It runs standard software. That means you don't have to re-write everything to support clustered solutions.
Lots of people don't understand that a 1024-processor beowulf won't run battlefield 1942 (if you've ever played it, you understand what I'm talking about), because it's not like a 2-processor workstation box. You have to write your software so that discrete pieces can be offloaded to other nodes and have the results posted back. A beowulf cluster is similar to SETI@Home or whatever distributed computing project you like. Though the interconnects are faster, the general idea behind how the software works is similar.
With this SGI system, it's like a 2-processor workstation on steroids. You can run standard multi-threaded code on it and actually use 1024 processors (and could possibly run battlefield 1942).
No, because $/MIPS is a misrepresentation. Heck, MIPS alone is meaningless, because all it does is take a theoretical maximum of CPU speed. MIPS doesn't take into account anything beyond CPU speed - like memory speed, backplanes, drive arrays, etc.
If you have heavily interrelated datasets, like in just about any thermal dynamics/plasma/weather problem, then there is so much interdependancy between adjacent "cells" that each work unit needs information from adjacent work units constantly. Spread that system out on a cluster solution and you're DOA because your communications between boxes are horrendously slow, with latencies measured in milliseconds instead of nanoseconds. So while you may have some absurd number of MIPS, the reality is that the CPUs are sitting idle 90% of the time waiting for data from some other CPU/memory block.
Take all those CPUs, all that memory, put them in a single box and do the backplanes and memory interfaces right (this is where the cost comes in by the way) and your latency becomes reasonable and you actually get all those MIPS.
It boils down to what the problem set is. If you need an obscene amount of transactions or have a highly interdependant problem set then you're better off with a single large box. If you can break up the problem set and minimize interactions then clustering is your friend.
There's also the issue of maintainance, and while the hardware costs may be lower for a large cluster, the time spent fixing the hundreds of boxes may kill you. Have a single box that's designed for redundancy and you'll pay a fortune for the support contract, but you won't spend an appreciable amount of your time on hardware support on the rare occasions it actually needs something.
In Intel's mind, the Itanium doesn't compete with the Opteron. Opteron will be at Xeon's throat, trying to tear up some of the 95% market share that xeon has in corporate and other mid-range servers.