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January 31st, 2008 - Adventures in Engineering — LiveJournal
The wanderings of a modern ronin.

Ben Cantrick
  Date: 2008-01-31 14:21
  Subject:   Multicore processors are here to stay, but memory is a bottleneck.
  Mood:der uber-nerd
  Music:Front Line Assembly - Terminal Power
  Tags:  reddit

And that's the situation today. Memory is much slower than processors and has been an essential bottleneck for fifteen years. Recently CPU speeds have stalled as well, limited now by power dissipation problems. As transistors switch, small inefficiencies convert a tiny bit of VCC to heat. And even an idle transistor leaks microscopic amounts of current. Small losses multiplied by hundreds of millions of devices means very hot parts.

Ironically, vast numbers of the transistors on a modern processor do nothing most of the time. No more than a single line of the cache is active at any time, most of the logic to handle hundreds of different instructions stands idle till infrequently needed, and page translation units that manage gigabytes handle a single word at a time.

But those idle transistors do convert the power supply to waste heat. The "transistors are free" mantra is now stymied by power concerns. So limited memory speeds helped spawn hugely complex CPUs, but the resultant heat has curbed clock rates, formerly the biggest factor that gave us faster computers every year.

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Ben Cantrick
  Date: 2008-01-31 14:42
  Subject:   McCain not actually a theocrat?
  Tags:  politics, reddit

"Yes, he's a social conservative, but his heart isn't in this stuff," one former aide told me, referring to McCain's instinctual unwillingness to impose on others his personal views about issues such as religion, sexuality, and abortion. "But he has to pretend [that it is], and he's not a good enough actor to pull it off. He just can't fake it well enough."


Holy crap. Did I just find myself thinking that McCain wouldn't be so bad??

Oh right, I forgot - he loves war and wants more of it.
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Ben Cantrick
  Date: 2008-01-31 14:43
  Subject:   Plane flys off conveyor belt. Now we have it on video.
  Tags:  reddit


Thank you MythBusters for doing the actual experiment and getting it all on video tape!

Also - IN YOUR FACE, "it won't fly"ers!!
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Ben Cantrick
  Date: 2008-01-31 16:33
  Subject:   Wow man... the colors, man.
  Tags:  reddit

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