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                | courses:mapreduce-tutorial:step-11 [2012/01/28 22:53] majlis Commands for execution were added.
 | courses:mapreduce-tutorial:step-11 [2012/01/31 09:39] (current) straka Change Perl commandline syntax.
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| wget --no-check-certificate 'https://wiki.ufal.ms.mff.cuni.cz/_media/courses:mapreduce-tutorial:step-5-solution1.txt' -O 'step-11-wc-without-combiner.pl' | wget --no-check-certificate 'https://wiki.ufal.ms.mff.cuni.cz/_media/courses:mapreduce-tutorial:step-5-solution1.txt' -O 'step-11-wc-without-combiner.pl' | 
| rm -rf step-11-out-wout; time perl step-11-wc-without-combiner.pl run /home/straka/wiki/cs-text-medium/ step-11-out-wout | # NOW EDIT THE FILE | 
|  | # $EDITOR step-11-exercise.pl | 
|  | rm -rf step-11-out-wout; time perl step-11-wc-without-combiner.pl /home/straka/wiki/cs-text-medium/ step-11-out-wout | 
| less step-11-out-wout/part-* | less step-11-out-wout/part-* | 
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| wget --no-check-certificate 'https://wiki.ufal.ms.mff.cuni.cz/_media/courses:mapreduce-tutorial:step-11-solution.txt' -O 'step-11-wc-with-perl-hash.pl' | wget --no-check-certificate 'https://wiki.ufal.ms.mff.cuni.cz/_media/courses:mapreduce-tutorial:step-11-solution.txt' -O 'step-11-wc-with-perl-hash.pl' | 
| rm -rf step-11-out-with-hash; time perl step-11-wc-with-perl-hash.pl run /home/straka/wiki/cs-text-medium/ step-11-out-with-hash | # NOW VIEW THE FILE | 
|  | # $EDITOR step-11-solution.pl | 
|  | rm -rf step-11-out-with-hash; time perl step-11-wc-with-perl-hash.pl /home/straka/wiki/cs-text-medium/ step-11-out-with-hash | 
| less step-11-out-with-hash/part-* | less step-11-out-with-hash/part-* | 
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| This is even more obvious with larger input data: | This is even more obvious with larger input data: | 
| ^ Script ^ Time to complete on ''/home/straka/wiki/cs-text'' ^ Commands ^ | ^ Script ^ Time to complete on ''/home/straka/wiki/cs-text'' ^ Commands ^ | 
| | {{:courses:mapreduce-tutorial:step-5-solution1.txt|step-11-wc-without-combiner.pl}} | 5mins, 4sec | <html><pre>wget --no-check-certificate 'https://wiki.ufal.ms.mff.cuni.cz/_media/courses:mapreduce-tutorial:step-5-solution1.txt' -O 'step-11-wc-without-combiner.pl'<br>rm -rf step-11-out-wout; time perl step-11-wc-without-combiner.pl run /home/straka/wiki/cs-text/ step-11-out-wout</pre></html> | | | {{:courses:mapreduce-tutorial:step-5-solution1.txt|step-11-wc-without-combiner.pl}} | 5mins, 4sec | <html><pre>wget --no-check-certificate 'https://wiki.ufal.ms.mff.cuni.cz/_media/courses:mapreduce-tutorial:step-5-solution1.txt' -O 'step-11-wc-without-combiner.pl'<br>rm -rf step-11-out-wout; time perl step-11-wc-without-combiner.pl /home/straka/wiki/cs-text/ step-11-out-wout</pre></html> | | 
| | {{:courses:mapreduce-tutorial:step-10.txt|step-11-wc-with-combiner.pl}} | 5mins, 33sec  | <html><pre>wget --no-check-certificate 'https://wiki.ufal.ms.mff.cuni.cz/_media/courses:mapreduce-tutorial:step-10-solution.txt' -O 'step-11-wc-with-combiner.pl'<br>rm -rf step-11-out-with-combiner; time perl step-11-wc-with-combiner.pl run /home/straka/wiki/cs-text/ step-11-out-with-combiner</pre></html>| | | {{:courses:mapreduce-tutorial:step-10.txt|step-11-wc-with-combiner.pl}} | 5mins, 33sec  | <html><pre>wget --no-check-certificate 'https://wiki.ufal.ms.mff.cuni.cz/_media/courses:mapreduce-tutorial:step-10.txt' -O 'step-11-wc-with-combiner.pl'<br>rm -rf step-11-out-with-combiner; time perl step-11-wc-with-combiner.pl /home/straka/wiki/cs-text/ step-11-out-with-combiner</pre></html>| | 
| | {{:courses:mapreduce-tutorial:step-11-solution.txt|step-11-wc-with-perl-hash.pl}} | 2mins, 24sec | <html><pre>wget --no-check-certificate 'https://wiki.ufal.ms.mff.cuni.cz/_media/courses:mapreduce-tutorial:step-11-solution.txt' -O 'step-11-wc-with-perl-hash.pl'<br>rm -rf step-11-out-with-perl-hash; time perl step-11-wc-with-perl-hash.pl run /home/straka/wiki/cs-text/ step-11-out-with-perl-hash</pre></html>| | | {{:courses:mapreduce-tutorial:step-11-solution.txt|step-11-wc-with-perl-hash.pl}} | 2mins, 24sec | <html><pre>wget --no-check-certificate 'https://wiki.ufal.ms.mff.cuni.cz/_media/courses:mapreduce-tutorial:step-11-solution.txt' -O 'step-11-wc-with-perl-hash.pl'<br>rm -rf step-11-out-with-perl-hash; time perl step-11-wc-with-perl-hash.pl /home/straka/wiki/cs-text/ step-11-out-with-perl-hash</pre></html>| | 
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| | Wordcount with combiner | 1min, 51sec | 51MB | | | Wordcount with combiner | 1min, 51sec | 51MB | | 
| | Wordcount with hash in mapper | 1min, 14sec | 51MB | | | Wordcount with hash in mapper | 1min, 14sec | 51MB | | 
| Using the combiner is beneficial, although manually combining the word occurrences in mapper manually is still faster. | Using the combiner is beneficial, although combining the word occurrences in mapper manually is still faster. | 
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|  | ---- | 
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|  | <html> | 
|  | <table style="width:100%"> | 
|  | <tr> | 
|  | <td style="text-align:left; width: 33%; "></html>[[step-10|Step 10]]: Combiners.<html></td> | 
|  | <td style="text-align:center; width: 33%; "></html>[[.|Overview]]<html></td> | 
|  | <td style="text-align:right; width: 33%; "></html>[[step-12|Step 12]]: Additional output from mappers and reducers.<html></td> | 
|  | </tr> | 
|  | </table> | 
|  | </html> |