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<div style="font-size: 14px; font-family: Calibri, sans-serif; ">Interesting how in the consumer PC world, they're starting to realize the challenge of effectively parallelizing. This article talks about the whole cores vs speed thing, since they theorize
a power dissipation limit results in speed*#of cores = constant.</div>
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<div style="font-size: 14px; font-family: Calibri, sans-serif; "><a href="http://www.marco.org/2013/08/10/ivy-bridge-ep-prices">http://www.marco.org/2013/08/10/ivy-bridge-ep-prices</a></div>
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<div style="font-size: 14px; font-family: Calibri, sans-serif; ">"<span class="Apple-style-span" style="color: rgb(34, 34, 34); font-size: 17px; line-height: 27px; font-family: elena-web, Elena, Georgia, serif; ">Many applications still only max out one or
two cores effectively, so for most usage, a higher clock speed is better than more cores if you can’t have both. But for highly parallelizable tasks, such as video processing, 3D rendering, and scientific research,…"</span></div>
<div style="font-size: 14px; font-family: Calibri, sans-serif; "><span class="Apple-style-span" style="color: rgb(34, 34, 34); font-size: 17px; line-height: 27px; font-family: elena-web, Elena, Georgia, serif; ">"</span><span class="Apple-style-span" style="color: rgb(34, 34, 34); font-size: 17px; line-height: 27px; font-family: elena-web, Elena, Georgia, serif; ">And
for all of those applications that <em>don’t</em> parallelize well (hi, Adobe and <a href="http://lame.sourceforge.net/" style="color: rgb(181, 25, 14); ">LAME</a>!), the higher-core, lower-clocked, more-expensive CPUs will probably perform <em>worse</em> than
the cheaper, fewer-core, higher-clocked ones."</span></div>
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<div><span class="Apple-style-span" style="color: rgb(34, 34, 34); line-height: 27px; ">Amdahl's law strikes again <grin></span></div>
<div><span class="Apple-style-span" style="color: rgb(34, 34, 34); line-height: 27px; ">And I wonder how many of those video processing, 3D rendering, and scientific research tasks actually have off the shelf user applications that can effectively use multiple
cores? Not everyone is coding up their own solutions, particularly for a MacPro (the subject of the article). I'm also not sure that parallelizing into N cores running at X/N clock rate is faster than running 1 core at X clock rate. If you are rendering
animation frames (and for a lot of Finite Element codes) there's a certain number of arithmetic operations to be done to get the job done, and whether you do N parallel streams at 1/N rate or 1 stream at full rate doesn't matter.</span></div>
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<div><span class="Apple-style-span" style="color: rgb(34, 34, 34); line-height: 27px; ">Potentially, of course, once you bite the bullet to parallelize, and you do it in a scalable manner, then, you can presumably scale to architectures where you have N cores
running at full speed (e.g. A classic cluster). I wonder, though, whether the end-user applications codes actually do that, or whether they design for the "single user on a single box" model. That is, they design to use multiple cores in the same box,but
don't really design for multiple boxes, in terms of concurrency, latency between nodes, etc.</span></div>
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<span style="color: rgb(31, 73, 125); ">James Lux, P.E.<o:p></o:p></span></p>
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<span style="color: rgb(31, 73, 125); ">Task Manager, FINDER – Finding Individuals for Disaster and Emergency Response<o:p></o:p></span></p>
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<span style="color: rgb(31, 73, 125); ">Co-Principal Investigator, SCaN Testbed (</span><i>née</i><span style="color: rgb(31, 73, 125); "> CoNNeCT) Project<o:p></o:p></span></p>
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<span style="color: rgb(31, 73, 125); ">Jet Propulsion Laboratory<o:p></o:p></span></p>
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<span style="color: rgb(31, 73, 125); ">4800 Oak Grove Drive, MS 161-213<o:p></o:p></span></p>
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<span style="color: rgb(31, 73, 125); ">Pasadena CA 91109<o:p></o:p></span></p>
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<span style="color: rgb(31, 73, 125); ">+(818)354-2075<o:p></o:p></span></p>
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