org.apache.hadoop.examples
Class RandomWriter
java.lang.Object
org.apache.hadoop.conf.Configured
org.apache.hadoop.examples.RandomWriter
- All Implemented Interfaces:
- Configurable, Tool
public class RandomWriter
- extends Configured
- implements Tool
This program uses map/reduce to just run a distributed job where there is
no interaction between the tasks and each task write a large unsorted
random binary sequence file of BytesWritable.
In order for this program to generate data for terasort with 10-byte keys
and 90-byte values, have the following config:
test.randomwrite.min_key
10
test.randomwrite.max_key
10
test.randomwrite.min_value
90
test.randomwrite.max_value
90
test.randomwrite.total_bytes
1099511627776
Equivalently, RandomWriter
also supports all the above options
and ones supported by GenericOptionsParser
via the command-line.
Method Summary |
static void |
main(String[] args)
|
int |
run(String[] args)
This is the main routine for launching a distributed random write job. |
Methods inherited from class java.lang.Object |
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait |
RandomWriter
public RandomWriter()
run
public int run(String[] args)
throws Exception
- This is the main routine for launching a distributed random write job.
It runs 10 maps/node and each node writes 1 gig of data to a DFS file.
The reduce doesn't do anything.
- Specified by:
run
in interface Tool
- Parameters:
args
- command specific arguments.
- Returns:
- exit code.
- Throws:
IOException
Exception
main
public static void main(String[] args)
throws Exception
- Throws:
Exception
Copyright © 2009 The Apache Software Foundation