Is Data locality concept applicable for Reducers also

Question

The concept of Data locality applies only to Mapper only as it deals with input files.

Is Reducers also will use Data locality concept while processing?

Data locality:

Data locality refers to the processing of the data where it resides by bringing the computation to the data, rather than requesting data from its location.

1. While computing the data, Mappers and Reducers work.

2. Mappers use Data locality while computing the data.

3. Reducers take input as Mappers output.

Assuming that Mappers output (intermediate data) stored in different data nodes.

Are Reducers use Data locality while computing?

Answer 1

No, Data-Locality concept applies to MAPPERS only.

Reducers are assigned based on partitioner logic (on unique keys of MAP outputs)