SGI Demos 64-Proc Linux Box
foobar104 writes "Details are scarce, but SGI announced this morning that their prototype Itanium 2 system has demonstrated more than 120 GB/s to and from main memory on the STREAM TRIAD benchmark, which is the fourth best result in the world. For comparison, the Cray C90 sustains 105 GB/s, while an even larger Sun Fire 15K clocks a measly 55 GB/s. The interesting part? The system wasn't running IRIX, SGI's proprietary version of UNIX. It was running Linux. More information on STREAM TRIAD, including results from other systems, is available here. The system, incidentally, was an Origin 3800 straight out of manufacturing equipped with Itanium 2 processor modules. SGI will start selling the systems early next year."
That was my first though. So it beats a C90, but what is faster?
Found the answer here.
And if you were wondering about a Beowolf cluster of these, the top ten ranking excludes "cluster results".
Linux running at 120 GB/s with 64 processors is impressive for an OS that has been criticized as inefficient when running on more than 8.
I would be very interested to know what version of the kernel they are using.
They also mention the SV1, which is a "low-end" Cray. I'm curious how the new X1 (nee SV2) does on the STREAM suite.
It's good to see that their "scalable linux" work seems to be doing pretty well! I'm sure it was much easier for them to use the IA-64 port of Linux than to port IRIX...
This sounds very cool, but I would really like more info than this. Plus, it isn't going to be released until next year. Within that time frame there will be the usual delays and then final release to a couple customers. Don't get me wrong, I think this is cool. Especially the linux part. This could go a long way to helping Linux scale better on massive machines.
The second thought is: can it be partitioned? This is a rather big machine and goes against the trend I have witnessed to use many smaller machines to accomplish your goal. I'll have to ask some of the guys at Oracle if they've looked at Linux installs of this size, but as far as I know they only make x86 ports right now. So, I wonder what linux apps would someone run on a system this big? (I know. Insert obligatory Quake, Beowolf and porn server reference here.)
Disclaimer: I work for an SGI competitor. But I have personally installed Linux on every piece of harware I can get my hands on. Just to play usually, but still. They just pay my mortgage.
_damnit_
It's my job to freeze you. -- Logan's Run
The whole point with the SGI supercomputers (there are Origin servers running Irix on 1024 processors) is that there's one single copy of the OS running across all those CPUs, and the entire memory is available to all CPUs on the same piece of hardware. That means, any CPU can access any piece of information at the speed of mem-IO, and you can easily create a large matrix (think many tens or hundreds of GB) to keep all your data in one piece.
Networked clusters (Mosix, Beowulf) split the CPU bunch across the network, and the memory is split too. That means there's a huge latency when a CPU wants to access data that happens to be on a different node on the network: the network latency is many times larger than memory latency.
There are problems that simply cannot be solved on networked clusters, precisely because of network latency. While true supercomputers (all CPUs on the same machine) do not have this limitation.
Well, ok, so you can split the matrix across nodes in a Beowulf, but even if you have the same CPU power as the SGI supercomp, you're going to solve the problem several times slower (if not several orders of magnitude slower). Such is the importance of latency.
This is why there's no point in clusterising this kind of computers: you lose their biggest advantage: single OS copy, all memory on the same machine.
SGI never thought to replace Irix with Windows! That's ridiculous. :-)
Irix can scale up to 1024 CPUs and beyond. Solaris can scale up to 100. Here's Linux, now it's scaling close to 100. How much to you think Windows can scale? 10 CPUs? 20?
SGI's thing was always that it had machines running one single copy of the OS across hundreds (or thousands) of CPUs on the same machine (not in a cluster). You simply cannot do that with Windows, period.
They had some graphics workstations running Windows, but that was on the lowest end of things, and now those systems are not available anymore.