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Unformatted text preview: ed speedup of 7.1. In fact the actual speedup was higher: ½½ ½ ¾¾ , due to inaccuracies in the proﬁling measurements for the initial version. We were able to gain a large speedup because sorting constituted a very large fraction of the overall execution time. Amdahl’s Law describes a general principle for improving any process. In addition to applying to speeding up computer systems, it can guide company trying to reduce the cost of manufacturing razor blades, or to a student trying to improve his or her gradepoint average. Perhaps it is most meaningful in the world of computers, where we routinely improve performance by factors of two or more. Such high factors can only be obtained by optimizing a large part of the system. 5.16 Summary
Although most presentations on code optimization describe how compilers can generate efﬁcient code, much can be done by an application programmer to assist the compiler in this task. No compiler can replace an inefﬁcient algorithm or data structure by a good one, an...
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- Spring '10
- The American