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> so that 'should' give a factor of over 64 No, that's not how trends work. You can't establish a trend from just two data points. And, given a trend, you can'

by phaemon 11y ago

> so that 'should' give a factor of over 64 No, that's not how trends work. You can't establish a trend from just two data points. And, given a trend, you can't just pick two points and say they should be so far apart. The only way that would work is if all the data points were very close to the trendline. And the only way that would happen is if CPU development happened very smoothly; which it doesn't. You have spurts of performance increase as new architectures are released. The only thing I was showing with those two figures was that it's clearly not true that speed stopped increasing in 2005. If you want to show there's a different trend, then you need multiple data points and compare the recent trend with the longer term trend to see if they're significantly different.

sliken 11y ago
Right, lies, damn lies, and statistics. You could pick data points to make either case. However if you plot transistor density, performance, clock speed, flops/watt, or other metric people attribute to moore's law you'll find the curve isn't holding. Improvements aren't stopping, but aren't doubling every 18 months either. Take for instance 3 generations of intel chips (Sandy Bridge, Ivy bridge and Haswell), Nvidia GPUs, or Arm chips. Sure a new feature might do encryption, floating point, or some unusual graphic feature twice as well, but that's small fraction of the normal use case for that chip. It's gotten so bad that nvidia often just renamed the chip, not actually revising the silicon between generations. Arm's new 64-bit generation of CPUS (cortex a53 and a57) aren't improving much at all over last years arm cores. Intel's new GPUs (one of the most parallel friendly workloads) aren't much better than 2 generations ago. Compare the best of the HD6000 intel GPUs to the old HD4000 2 genrations ago. So by exactly what metric can support the idea that Moore's law isn't dead? Clockspeed? Performance? Transistor budget? Number of cores? What today (april 2015) is 8 times better than 4.5 years ago?

by phaemon 11y ago

sliken 11y ago

Right, lies, damn lies, and statistics. You could pick data points to make either case. However if you plot transistor density, performance, clock speed, flops/watt, or other metric people attribute to moore's law you'll find the curve isn't holding. Improvements aren't stopping, but aren't doubling every 18 months either. Take for instance 3 generations of intel chips (Sandy Bridge, Ivy bridge and Haswell), Nvidia GPUs, or Arm chips. Sure a new feature might do encryption, floating point, or some unusual graphic feature twice as well, but that's small fraction of the normal use case for that chip. It's gotten so bad that nvidia often just renamed the chip, not actually revising the silicon between generations. Arm's new 64-bit generation of CPUS (cortex a53 and a57) aren't improving much at all over last years arm cores. Intel's new GPUs (one of the most parallel friendly workloads) aren't much better than 2 generations ago. Compare the best of the HD6000 intel GPUs to the old HD4000 2 genrations ago. So by exactly what metric can support the idea that Moore's law isn't dead? Clockspeed? Performance? Transistor budget? Number of cores? What today (april 2015) is 8 times better than 4.5 years ago?