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| | NOTES ON PARALLEL ALGORITHMS (Site not responding. Last check: 2007-10-20) |
 | | Compare this to the sequential approach: we would take n-1 steps to sum all the numbers, as opposed to 3 -- which is lg 8, and not by accident: each parallel step halves the number of results, so in lg n steps we are down to 1 result. |
 | | The speedup for addition of 2p = 8 numbers as above will be 7/3 = 2.333. |
 | | But if we buy one million processors, and add two million numbers, the speedup is (roughly) 1,000,000/21, which is about 50,000 times faster than the sequential method. |
| www.cs.umd.edu /class/spring2000/cmsc251/notes/par.html (476 words) |
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