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Please. This is not relevant almost 12 years later! Moore's law is saturating. Benchmarks numbers are more and more a function of core-count not GHz-count. It'

by fizixer 12y ago

Please. This is not relevant almost 12 years later! Moore's law is saturating. Benchmarks numbers are more and more a function of core-count not GHz-count. It's time to embrace the RISC-y tiny speed-demon cores (so you can have them by the dozens) over complex brainiac ones (too much space). It's been almost 9 years Intel introduced dual cores and the mainstream is still quad-core (with 6 and 8 on the fringes) while GHz is less that what P4 had more than 10 years ago! What is going on? If Moore's law still holds, in 9 years since 2005 Intel should be at 24/32/48 core ballpark, something that is clearly not the case. In that vein I would also state that linux needs a major overhaul, i.e., to shift itself from a single core kernel to one that leverages n-cores. good read: http://www.lighterra.com/papers/modernmicroprocessors/ http://www.lighterra.com/papers/modernmicroprocessors/

mikeash 12y ago
Moore's Law is only about transistor density. Any relationship to clock speed or core count is merely because of how transistor density can enable those. If you look at transistor density, Moore's Law has held up fine so far. There's no "if," it has held.
- fizixer 12y ago
  So here's the transistor count from 2004 and 2014: - 2004: Pentium 4 on 112 mm2 die: 125M transistors [0] - 2014: Core i7 177 mm2 die: 1.4B transistors [1] let's scale the P4 count up to 177 mm2 die so we can make a better comparison: - 2004: Pentium 4 on 177 mm2 die: ~200M - 2014: Core i7 on 177 mm2 die: 1.4B transistors on the surface it looks like a lot of progress in 10 years, 7 fold increase in transistor count. But we're talking about an exponential law, doubling of count every two years. This is what it should've given us: - 2006: 400M - 2008: 800M - 2010: 1.6B - 2012: 3.2B - 2014: 6.4B - 2016: 12.8B ... !!! if we consider 3 years to be the doubling time instead of two years (which is already a failure of Moore's law that originally stated 18 months) we should get this: - 2007: 400M - 2010: 800M - 2013: 1.6B - 2016: 3.2B not only we were not at 1.6 billion transistors a year ago, I don't think Intel has any announcement that they'll be at 3.2 billion (on a 177 mm2 die equivalent) a year an a half from today. But who counts the transistors? if Intel itself, then I'm afraid I can't take it very seriously. Then what other measure do we have? benchmarks mostly. Unfortunately the problem with the benchmarks is that over the years, the auxiliary hardware improves a lot not just the processor. So not a lot of processor improvement still results in overall system speed up due to other components. For example, during P4 days the RAM fronts side bus was a lot slower than it is on the latest motherboard with latest RAM and Core-i7. And not a lot of people are interested in benchmarking a P4 with latest motherboard and RAM, cz for one thing it's very difficult to set things up, and secondly, you're only annoying a silicon valley giant as a result, not a very good marketing strategy. I'm willing to bet if you can make a 2004 P4 run on modern motherboard and ram, and then compare it to 2013 Haswell, the single core performance would be meh at best, and multi-core performance would be more like linear (even sub-linear) rather than exponential. Moore's law has become quite a marketing gimmick over the past few years and public seems to be okay with it. interesting read: http://spectrum.ieee.org/semiconductors/devices/the-status-of-moores-law-its-complicated http://spectrum.ieee.org/semiconductors/devices/the-status-o... [0] http://en.wikipedia.org/wiki/List_of_Intel_Pentium_4_microprocessors#Prescott_.2890.C2.A0nm.29_2 http://en.wikipedia.org/wiki/List_of_Intel_Pentium_4_micropr... [1] http://en.wikipedia.org/wiki/Haswell_(microarchitecture)#Desktop_processors http://en.wikipedia.org/wiki/Haswell_(microarchitecture)#Des...
  - mattnewport 12y ago
    We've probably seen a bit of a slow down in Moore's law over the last 10 years, at least when it comes to Intel CPUs but I think you're exaggerating the extent of the slowdown. Some benchmarks are heavily dependent on RAM latency and / or bandwidth but improvements in those have been slower than improvements in CPU performance and if CPU performance is what you're interested in then pick a benchmark that is largely independent of main memory (a compute bound benchmark whose working set fits in L2). Haswell will still do a lot better than a P4 in a compute bound benchmark, perhaps even beating it by more than in a memory bound benchmark. The other thing to consider is that over time more attention is being paid to performance per Watt than raw FLOPS and in that regard Haswell looks rather better compared to the P4.
    - fizixer 12y ago
      Okay I've done some thinking/browsing and I've come up with an approximate way to figure out (edit: relative) Moore's law progress without relying on official transistor count by Intel: 1 - Take this Haswell image (Intel claim: 2.6 billion in 355 mm2): http://images.anandtech.com/doci/8426/HSW-E%20Die%20Mapping%20Hi-Res.jpg http://images.anandtech.com/doci/8426/HSW-E%20Die%20Mapping%... (source: http://www.anandtech.com/show/8426/the-intel-haswell-e-cpu-review-core-i7-5960x-i7-5930k-i7-5820k-tested http://www.anandtech.com/show/8426/the-intel-haswell-e-cpu-r...) 2 - Take this Prescott 2M image (Intel claim: 169 million in 135 mm2): http://images.anandtech.com/reviews/cpu/intel/pentium4/6xx/prescott2m.jpg http://images.anandtech.com/reviews/cpu/intel/pentium4/6xx/p... (source: http://www.anandtech.com/show/1621/3 http://www.anandtech.com/show/1621/3) 3 - Process these images: remove extra text and resize one so that the ratio of the areas of the two dies is 355 to 135. 4 - Extract one core from Haswell (e.g., top left one) 5 - Remove the per-core cache (e.g., top left square in the top left core) 6 - Estimate the area of the resulting core. 7 - For Prescott, remove the visible left side (which is L2 cache) 8 - Remove about 30% from the top, likely overhead of the Netburst architecture (not present in the Haswell core) (you might disagree with this step in which case, you can do the calculation without removing it as well) 9 - Estimate the area of this. 10 - The number in step 6 (area-6) should be smaller than in step 9 (area-9) and would represent the true shrinkage over 4 technology nodes. 11 - area-9 divided by area-6 is the percentage of transistor-count-increase over 4 nodes. This wouldn't give absolute numbers and won't corroborate Intel's quotes for either Haswell or Prescott. But it will give the ratio which can be compared with the claim of going from 90nm to 22nm, i.e., 4 generations, over 8 years. According to which the percentage in step 11 should be 2^4 = 16 = 1600% (My guess: it would be way less than 1600%) even ignoring the fact that the time difference between two articles is 9.5 years instead of 8. (P.S.: I don't have time atm but I'll try to do this myself)

by fizixer 12y ago

mikeash 12y ago

Moore's Law is only about transistor density. Any relationship to clock speed or core count is merely because of how transistor density can enable those. If you look at transistor density, Moore's Law has held up fine so far. There's no "if," it has held.

fizixer 12y ago
So here's the transistor count from 2004 and 2014: - 2004: Pentium 4 on 112 mm2 die: 125M transistors [0] - 2014: Core i7 177 mm2 die: 1.4B transistors [1] let's scale the P4 count up to 177 mm2 die so we can make a better comparison: - 2004: Pentium 4 on 177 mm2 die: ~200M - 2014: Core i7 on 177 mm2 die: 1.4B transistors on the surface it looks like a lot of progress in 10 years, 7 fold increase in transistor count. But we're talking about an exponential law, doubling of count every two years. This is what it should've given us: - 2006: 400M - 2008: 800M - 2010: 1.6B - 2012: 3.2B - 2014: 6.4B - 2016: 12.8B ... !!! if we consider 3 years to be the doubling time instead of two years (which is already a failure of Moore's law that originally stated 18 months) we should get this: - 2007: 400M - 2010: 800M - 2013: 1.6B - 2016: 3.2B not only we were not at 1.6 billion transistors a year ago, I don't think Intel has any announcement that they'll be at 3.2 billion (on a 177 mm2 die equivalent) a year an a half from today. But who counts the transistors? if Intel itself, then I'm afraid I can't take it very seriously. Then what other measure do we have? benchmarks mostly. Unfortunately the problem with the benchmarks is that over the years, the auxiliary hardware improves a lot not just the processor. So not a lot of processor improvement still results in overall system speed up due to other components. For example, during P4 days the RAM fronts side bus was a lot slower than it is on the latest motherboard with latest RAM and Core-i7. And not a lot of people are interested in benchmarking a P4 with latest motherboard and RAM, cz for one thing it's very difficult to set things up, and secondly, you're only annoying a silicon valley giant as a result, not a very good marketing strategy. I'm willing to bet if you can make a 2004 P4 run on modern motherboard and ram, and then compare it to 2013 Haswell, the single core performance would be meh at best, and multi-core performance would be more like linear (even sub-linear) rather than exponential. Moore's law has become quite a marketing gimmick over the past few years and public seems to be okay with it. interesting read: http://spectrum.ieee.org/semiconductors/devices/the-status-of-moores-law-its-complicated http://spectrum.ieee.org/semiconductors/devices/the-status-o... [0] http://en.wikipedia.org/wiki/List_of_Intel_Pentium_4_microprocessors#Prescott_.2890.C2.A0nm.29_2 http://en.wikipedia.org/wiki/List_of_Intel_Pentium_4_micropr... [1] http://en.wikipedia.org/wiki/Haswell_(microarchitecture)#Desktop_processors http://en.wikipedia.org/wiki/Haswell_(microarchitecture)#Des...
- mattnewport 12y ago
  We've probably seen a bit of a slow down in Moore's law over the last 10 years, at least when it comes to Intel CPUs but I think you're exaggerating the extent of the slowdown. Some benchmarks are heavily dependent on RAM latency and / or bandwidth but improvements in those have been slower than improvements in CPU performance and if CPU performance is what you're interested in then pick a benchmark that is largely independent of main memory (a compute bound benchmark whose working set fits in L2). Haswell will still do a lot better than a P4 in a compute bound benchmark, perhaps even beating it by more than in a memory bound benchmark. The other thing to consider is that over time more attention is being paid to performance per Watt than raw FLOPS and in that regard Haswell looks rather better compared to the P4.
  - fizixer 12y ago
    Okay I've done some thinking/browsing and I've come up with an approximate way to figure out (edit: relative) Moore's law progress without relying on official transistor count by Intel: 1 - Take this Haswell image (Intel claim: 2.6 billion in 355 mm2): http://images.anandtech.com/doci/8426/HSW-E%20Die%20Mapping%20Hi-Res.jpg http://images.anandtech.com/doci/8426/HSW-E%20Die%20Mapping%... (source: http://www.anandtech.com/show/8426/the-intel-haswell-e-cpu-review-core-i7-5960x-i7-5930k-i7-5820k-tested http://www.anandtech.com/show/8426/the-intel-haswell-e-cpu-r...) 2 - Take this Prescott 2M image (Intel claim: 169 million in 135 mm2): http://images.anandtech.com/reviews/cpu/intel/pentium4/6xx/prescott2m.jpg http://images.anandtech.com/reviews/cpu/intel/pentium4/6xx/p... (source: http://www.anandtech.com/show/1621/3 http://www.anandtech.com/show/1621/3) 3 - Process these images: remove extra text and resize one so that the ratio of the areas of the two dies is 355 to 135. 4 - Extract one core from Haswell (e.g., top left one) 5 - Remove the per-core cache (e.g., top left square in the top left core) 6 - Estimate the area of the resulting core. 7 - For Prescott, remove the visible left side (which is L2 cache) 8 - Remove about 30% from the top, likely overhead of the Netburst architecture (not present in the Haswell core) (you might disagree with this step in which case, you can do the calculation without removing it as well) 9 - Estimate the area of this. 10 - The number in step 6 (area-6) should be smaller than in step 9 (area-9) and would represent the true shrinkage over 4 technology nodes. 11 - area-9 divided by area-6 is the percentage of transistor-count-increase over 4 nodes. This wouldn't give absolute numbers and won't corroborate Intel's quotes for either Haswell or Prescott. But it will give the ratio which can be compared with the claim of going from 90nm to 22nm, i.e., 4 generations, over 8 years. According to which the percentage in step 11 should be 2^4 = 16 = 1600% (My guess: it would be way less than 1600%) even ignoring the fact that the time difference between two articles is 9.5 years instead of 8. (P.S.: I don't have time atm but I'll try to do this myself)