The input sampler should generate a small, random sample of the input, saved to a file.
The partitioner should read the sample file and partition keys into relatively even-sized key-ranges, where the partition numbers correspond to key order.
Note that when the sampler is used for partitioning, the number of samples required is proportional to the number of reduce partitions. 10x the intended reducer count should give good results.
New Feature
Closed
Major
want input sampler & sorted partitioner
