Slashdot Mirror
Windows Cluster Hits a Petaflop, But Linux Retains Top-5 Spot
Twice a year, Top500.org publishes a list of supercomputing benchmarks from sites around the world; the new results are in. Reader jbrodkin writes "Microsoft says a Windows-based supercomputer has broken the petaflop speed barrier, but the achievement is not being recognized by the group that tracks the world's fastest supercomputers, because the same machine was able to achieve higher speeds using Linux. The Tokyo-based Tsubame 2.0 computer, which uses both Windows and Linux, was ranked fourth in the world in the latest Top 500 supercomputers list. While the computer broke a petaflop with both operating systems, it achieved a faster score with Linux, denying Microsoft its first official petaflop ranking."
Also in Top-500 news, reader symbolset writes with word that "the Chinese Tianhe-1A system at the National Supercomputer Center in Tianjin takes the top spot with 2.57 petaflops. Although the US has long held a dominant position in the list things now seem to be shifting, with two of the top spots held by China, one by Japan, and one by the US. In the Operating System Family category Linux continues to consolidate its supercomputing near-monopoly with 91.8% of the systems — up from 91%. High Performance Computing has come a long way quickly. When the list started as a top-10 list in June of 1993 the least powerful system on the list was a Cray Y-MP C916/16526 with 16 cores driving 13.7 RMAX GFLOP/s. This is roughly the performance of a single midrange laptop today."
Yeah, but on the downside, it means that asian chicks are going to start gaining weight and wanting to be "liberated" and stuff, so your sexy accent isn't really going to pay off.
Even more interesting is the fact that GPGPU accelerated supercomputers are clearly outclassing classical supercomputers such as Cray
Funny that you mention Cray, as the Cray-1 was the first supercomputer with vector processors, what GPGPUs actually are.
I have discovered a truly marvelous proof of killer sig, which this margin is too narrow to contain.
> Linux isn't exactly an ultrascalable high-performance OS either.
Actually it is, it has a whole mess of features that don't become relevant until high-end stuff that the typical "haha lunix sux0rs" sad windoze weenie couldn't comprehend. It's retrogressed slightly lately out-of-box under neverrending low-end "schedule better for the desktop" pressure (hint: if you have 32768 cores, O(1) scheduling is *really handy*. Fortunately you can switch schedulers).
Coupled with the vendor-specific addons like SGI ProPack, it really is the least worst OS out there for HPC today.
Actually, flops means exactly what the OP said: Floating point operations per second.
Whenever in an argument, remember this.
I do scientific high-performance computing, and there is simply no reason anyone would want to run Windows on a supercomputer.
Linux has native, simple support for compiling the most common HPC languages (C and Fortran). It is open source and extensively customizable, so it's easy to make whatever changes need to be made to optimize the OS on the compute nodes, or optimize the communication latency between nodes. Adding support for exotic filesystems (like Lustre) is simple, especially since these file systems are usually developed *for* Linux. It has a simple, robust, scriptable mechanism for transferring large amounts of data around (scp/rsync) and a simple, unified mechanism for working remotely (ssh). Linux (the whole OS) can be compiled separately from source to optimize for a particular architecture (think Gentoo).
What advantage does Windows bring to a HPC project?
I am impressed that Windows can actually scale to that type of hardware. However, my questions are:
- What kind of performance can an actual program achieve on Windows on that hardware?
Fairly good if the programmer is skilled at writing super computer applications.
- Are context switches from godawful slow memory allocation calls as painfully slow on this supercomputer as they are on the typical desktop?
It shouldn't matter too much since they would (mostly) avoid context switches by only running 1 copy of the software per core and half of windows is disabled in Super Computing edition.
- How badly does the ever-essential anti-malware suite drag down the supercomputer?
Shouldn't be needed since it should be extremely hard for malware to get into such a controlled environment to begin with.
There are other reasons Microsoft's idea is a bad one such as the higher licensing costs, no possible reason to want to write custom, non GUI software from scratch on Windows etc.
You will probably laugh but banks and finances do not: Excel spreadsheets.
Microsoft HPC solution allows distribute it across many nodes.
Trust me: *huge* money are there (alas, not for you, not for me and not for science).
It's much cheaper for a bank to rent a supercomputer to calculate a heavy spreadsheet written by programming-challenged but money-wise CPA then to hire a money-challenged, HPC-wise guy to rewrite (and perpetually modify it on a short notice) this spreadsheet to FORTRAN.
Any other application built for windows has the same issue.
I work for a company doing modeling for insurance, and the software for catastrophe modeling (RMS, AIR, Eqecat,) all are windows only. The simulations and models take days to run for a large data set, and the software/modeling companies aren't about to switch off of windows for the software licensed from them, and there is nowhere else to go.
I'm a concientious
As a professional HPC programmer, using "days to run for a large data set" is absolutely meaningless to me.
Define large. Means different things to different people.
.