mongodb - Is there a combiner phase in Mongo DB's map reduce framework -


is there thing similar combiner (as in hadoop map reduce) in mongo db's map reduce framework. we're trying out map reduce framework in mongo db cluster, , there several rows key potentially combined before being sent reduce phase.

1 billion records i'm going map-reduce each record 100 bytes 100 records same key (map) on each node

wouldn't network b/w bottle neck such operation? understand result in lots of emits, avoided if there's mini reducer (say combiner) phase on each node, or understanding incorrect?

is there thing close combiner phase of hadoop map reduce, or if not, there similar planned later releases?

as current knowledge, there no combiner phase in mapreduce implementation of mongo. mongo implements different version of mr standard; if have performance issues, better using hadoop.

here have question discussing differences between mongo mr , hadoop.


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