mapreduce - Hadoop Map/Reduce Job distribution -

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I have 4 nodes and I'm running a maggie sample project to see if all 4 nodes work between I was attacked by Project Time and I found that, the Mapper function is being divided into all 4 nodes, but only one node is being done by the reducer function. Does it seem like this is reducer work, as it is split between all four nodes?

Thanks

The distribution of the mapers depends on the data of the mapper's data Operated on the block. The framework tries to assign tasks to a node by default, in which the blocks of data are stored. This will prevent network transfers of data.

Again it depends on the number for the reducer. If your job requires only one broadcast, then it can be assigned to any PF of the nodes.

This will also impact speculative execution. If then this is the result of many instances of the map or reduces the work to start work on different nodes and the job tracker is decided on the basis of completion, which passes through one and the other Examples will be killed.


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