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MapReduce Tutorial : Exercise - sorting
You are given data consisting of (31-bit integer, string data) pairs. These are available in plain text format:
Path | Size |
---|---|
/home/straka/hadoop/example-inputs/numbers-small | 3MB |
/home/straka/hadoop/example-inputs/numbers-medium | 184MB |
/home/straka/hadoop/example-inputs/numbers-large | 916MB |
You can assume that the integers are uniformly distributed.
Your task is to sort these data. Your solution should work for TBs of data. For that reason, you must use multiple reducers. If your job is executed using r reducers, the output consists of r files, which when concatenated would produce sorted (key, value) pairs. In other words, each of the output files contains sorted (integer, data) pairs and all keys in one file are either smaller or larger than in other file.
Nonuniform data
The
After solving
Path | Size |
---|---|
/home/straka/hadoop/example-inputs/nonuniform-small | 3MB |
/home/straka/hadoop/example-inputs/nonuniform-medium | 160MB |
/home/straka/hadoop/example-inputs/nonuniform-large | 797MB |
After you