- All Implemented Interfaces:
- org.apache.reef.tang.annotations.Name<Integer>
- Enclosing class:
- JobConf
@NamedParameter(doc="Hash range multiplier",
short_name="hash_range_multiplier",
default_value="10")
public final class JobConf.HashRangeMultiplier
extends Object
implements org.apache.reef.tang.annotations.Name<Integer>
Hash range multiplier.
If we need to split or recombine an output data from a task after it is stored,
we multiply the hash range with this factor in advance
to prevent the extra deserialize - rehash - serialize process.
In these cases, the hash range will be (hash range multiplier X destination task parallelism).
The reason why we do not divide the output into a fixed number is that the fixed number can be smaller than
the destination task parallelism.