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courses:mapreduce-tutorial:step-7 [2012/01/28 15:33] majlis |
courses:mapreduce-tutorial:step-7 [2012/01/29 20:52] straka |
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rm -rf step-7-out-sol; | rm -rf step-7-out-sol; | ||
less less step-7-out-sol/ | less less step-7-out-sol/ | ||
+ | Remarks: | ||
+ | * The reducers seem to start running before the mappers finish. In the web interface, the running time of reducers is divided into thirds: | ||
+ | * during the first 33%, the mapper outputs are copied to the machine where reducer runs | ||
+ | * during the second 33%, the (key, value) pairs are sorted | ||
+ | * during the last 33%, the user-defined reducer runs | ||
---- | ---- | ||
Line 33: | Line 37: | ||
</ | </ | ||
</ | </ | ||
+ |