---

orch.dryrun

Switches the execution platform between the local host and the Hadoop cluster. No changes in the R code are required for a dry run.

Usage

orch.dryrun(onoff)

Arguments

onoff

Set to TRUE to run a MapReduce program locally, or FALSE to run the program on the Hadoop cluster.

Usage Notes

The orch.dryrun function enables you to run a MapReduce program locally on a laptop using a small data set before running it on a Hadoop cluster using a very large data set. The mappers and reducers are run sequentially on row streams from HDFS. The Hadoop cluster is not required for a dry run.

Return Value

The current setting of orch.dryrun

See Also

hadoop.exec, hadoop.run

Example

This example changes the value of orch.dryrun from FALSE to TRUE.

R> orch.dryrun()
[1] FALSE
R> orch.dryrun(onoff<-T)
R> orch.dryrun()
[1] TRUE