TOP500 list by interconnect

While attending a Hot Interconnects talk on supercomputing, I got the following idea. The TOP500 site provides graphs of the number of systems and total performance per interconnect family, which shows an approximate measure of the popularity of the different interconnects. But how do they affect the performance of an individual system? Clearly, a high-performance interconnect should result in higher efficiency than a commodity one. But by how much? And which systems would use what type of interconnect?

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Tokina 11-16mm f/2.8 wide-angle lens

… or how to make a small space look huge.

I couldn’t resist, and bought another lens. This time a real wide-angle lens, the Tokina AF 11-16mm f/2.8 AT-X Pro DX. Yes, it’s a zoom lens, and on paper the range fitted nicely to my Tamron 17-50mm f/2.8. But the difference between 11 and 16mm turned out to be so tiny (and the image quality so good that cropping an 11mm image down to 16mm would be more than adequate), that I might as well have gotten a prime 11mm one. But still, a very nice lens this is!

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Practical Compressor Test

Welcome to the ‘Practical Compressor Test’. Unlike some other compressor comparison sites, I won’t be looking for a compressor offering for the last bit of compression. Instead I’ll try to find the most practical compressor out there. This means compression and decompression times are taken into account, so PAQAR and the like, which can achieve very good compression at the expense of insanely long run times (several hours on this benchmark!) are not considered.

Instead I’ll be focusing on very well known, established compressors that are easily obtained (I only use precompiled packages and won’t build from source) and have reasonable run times. Also I won’t try every combination of compression options but limit the test to one general option (-1 to -9 for gzip and bzip2, -m1 to -m5 for RAR, …).

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