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Japan Captures TOP500 Crown with Arm-Powered Supercomputer

top500.org

101–110 of 220 posts

Re: Japan Captures TOP500 Crown with Arm-Powered Supercomputer

#101

Anyone know the reason for the dominance of Power processors in the top 10 other than it's from IBM and they get a lot of contracts for HPC?

They're fast, have lots of memory and IO bandwidth and can do some cool other tricks (I can't remember the name right now, but they have thing for PCIe devices to participate in cache coherency, their in-system protocols scale better to more CPUs, ...)

Re: Japan Captures TOP500 Crown with Arm-Powered Supercomputer

#103
post #73
post #50

Really wish Fujitsu sold a developer kit with an A64fx chip - its the only shipping ARM chip with SVE that I know of and I would love to get my hands on one to play with.

No kidding! I don't have any sense of how much these cost to manufacture. There ought to be a market for a A64fx based rackmount server system. If the price isn't outrageous, I'd love to see these sold as an SBC.

Something like the Fujitsu PRIMEHPC FX700?

Re: Japan Captures TOP500 Crown with Arm-Powered Supercomputer

#104
post #16
post #8

Not to be dismissive, but can't anyone "build" the biggest supercomputer by reserving enough instances at AWS or GCP? I'm sure that AWS or GCP would like to encourage this competition, but it seems a bit, well, boring.

The ranking is calculated based on the Linpack benchmark. Being a parallel application, performance is not simply scaled to number of processors; the network interconnect is hugely important. Now, although Linpack is a better evaluation metric for a supercomputer than simply totaling up # of processors and RAM size, it's still a very specific benchmark of questionable real-world utility; people like it because it giv…

Linpack is pretty lightweight as far as benchmarks go. You need some memory bandwidth but not much network at all, just reduces which are pretty efficient. It's not a good proxy for the most challenging applications, but lives on because no one has a better alternative. Basically, these are the classes of problems: 1. compute bound, trivially parallel. These are like breaking RSA encryption, stuff that was done over the Internet 20 years ago even when links were much slower. Basically doesn't even need the proverbial Beowulf cluster. Linpack is basically in this category, so you could, with care, make a cloud machine to do it. 2. Memory-bandwidth bound, trivially parallel. Stuff like search engine index building, Still not hard to do over distributed networks, or, yes, commercial Ethernet in a Beowulf Cluster. 3. Network bound, coupled parallel. The most challenging category, can only be done with a single-site computer on a fast interconnect. And, as noted, "fast" here has a totally different meaning compared to commercial networking latencies, especially. Depending on the type of network, you can have a significant fraction of the total transistors in the machine in the interconnect. These networks are heavily optimized for specific MPI operations, such as All-to-All, where you might have 1 million cores. The reason is that the whole calculation, being coupled, moves as quickly as the slowest task on the slowest node. You see weird stuff like reserving an entire core just for communicating with the I/O system and handling OS interrupts, because otherwise the "jitter" of nodes randomly doing stuff slows down the entire machine.

Re: Japan Captures TOP500 Crown with Arm-Powered Supercomputer

#105

I cannot think of any plausible way in which Apple could have influenced the date of this announcement, but the timing, given what is expected to be announced later today, is uncanny.

As far as I remember the TOP500 list is updated more or less the same time every November and June. Google Trends agree[1].

[1]: https://trends.google.com/trends/explore?date=all&q=top500

Re: Japan Captures TOP500 Crown with Arm-Powered Supercomputer

#106

Earlier quoted context omitted.

Simple, human error and no code review process for your production environment. Something similar happened to a huge retailer here in Austria where just typing your username without password would log you in. Reason? An intern committed debug code to production and nobody noticed. In my book that's not the fault of the intern but the fault of the CTO/$TECH_LEAD that hasn't implemented and religiously uphold a code re…

It is the fault of both. Interns are not stupid and so they have to carry the burden of their mistakes too.

No, absolutely not. As an engineer you develop systems and processes that don’t allow such major mistakes.

You can’t fault people for making simple mistakes or you’ll end up with an organization where nothing gets done.

Re: Japan Captures TOP500 Crown with Arm-Powered Supercomputer

#107
Is there information on how the Fugaku machines are connected together? The highest performing Power9 ones seem to use InfiniBand, but is that still true with the ARM devices?

Edit: seems to be a Fujitsu designed interconnect [0]. Wonder how much of the overall performance is dependent on the difference in communication.

https://www.fujitsu.com/global/documents/solutions/business-...

Re: Japan Captures TOP500 Crown with Arm-Powered Supercomputer

#108
post #100

Earlier quoted context omitted.

Heheh, from the guys who use variables such as Vo ,tm,max_p, this guy expect them to RTFM.

Those are perfectly reasonable names since they're standard convention in engineering and science. It's like using i, j, and k for index variables in iterators; the meaning is clear due to convention.

As someone who started learning Python with Data Science and ML courses and tutorials I overused these short names for variables in my first web apps

Re: Japan Captures TOP500 Crown with Arm-Powered Supercomputer

#109
post #21

Earlier quoted context omitted.

To be fair, I wouldn't host my website on my world-class supercomputer either, if I had one...

To be even fairer, I've served a shit ton of traffic on a small DigitalOcean droplet and never had issues because my stack is reasonable.

But... We do realize the skills required to make and evaluate a super computers is vastly different from web serving right?

Sure some principals may be common due to the distributed network but the actual practical tools have nothing in common.

Re: Japan Captures TOP500 Crown with Arm-Powered Supercomputer

#110

Is there information on how the Fugaku machines are connected together? The highest performing Power9 ones seem to use InfiniBand, but is that still true with the ARM devices? Edit: seems to be a Fujitsu designed interconnect [0]. Wonder how much of the overall performance is dependent on the difference in communication. https://www.fujitsu.com/global/documents/solutions/business-...

I don't know whats the best reference, but here's one: https://www.fujitsu.com/global/Images/the-tofu-interconnect-...
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