Differences
This shows you the differences between two versions of the page.
Both sides previous revision Previous revision Next revision | Previous revision | ||
courses:mapreduce-tutorial:step-6 [2012/01/29 20:25] straka |
courses:mapreduce-tutorial:step-6 [2012/02/06 13:55] (current) straka |
||
---|---|---|---|
Line 4: | Line 4: | ||
So far all our Hadoop jobs were executed locally. But all of them can be executed on multiple machines. It suffices to add parameter '' | So far all our Hadoop jobs were executed locally. But all of them can be executed on multiple machines. It suffices to add parameter '' | ||
- | perl script.pl | + | perl script.pl -c number_of_machines [-w sec_to_wait_after_job_completion] input_directory output_directory |
This commands creates a cluster of specified number of machines. Every machine is able to run two mappers and two reducers simultaneously. In order to be able to observe the counters, status and error logs of the computation after it ends, parameter '' | This commands creates a cluster of specified number of machines. Every machine is able to run two mappers and two reducers simultaneously. In order to be able to observe the counters, status and error logs of the computation after it ends, parameter '' | ||
Line 17: | Line 17: | ||
===== Web interface ===== | ===== Web interface ===== | ||
- | The cluster master provides a web interface on port 50030 (the port may change in the future). The cluster master | + | The cluster master provides a web interface on address printed by the '' |
The web interface provides a lot of useful information: | The web interface provides a lot of useful information: | ||
Line 24: | Line 24: | ||
* for any job, the counters and outputs of all mappers and reducers | * for any job, the counters and outputs of all mappers and reducers | ||
* for any job, all Hadoop settings | * for any job, all Hadoop settings | ||
+ | |||
+ | |||
===== Example ===== | ===== Example ===== | ||
Line 29: | Line 31: | ||
Try running the {{: | Try running the {{: | ||
wget --no-check-certificate ' | wget --no-check-certificate ' | ||
- | rm -rf step-6-out; perl step-6-wordcount.pl | + | rm -rf step-6-out; perl step-6-wordcount.pl -c 1 -w 600 -Dmapred.max.split.size=1000000 / |
and explore the web interface. | and explore the web interface. | ||