rlink - Parallelization of REvaluate[]?

Is there a way to run several RLink computations via REvaluate[] in parallel, e.g. with ParallelTable[]?

Answer

It is actually possible, if you run several copies of RLink in parallel. This would mean several parallel kernels, R and JVM processes. Here is an example (I have 6 cores):

ParallelEvaluate[Needs["RLink`"]; RLink`InstallR[]]
ParallelEvaluate[RLink`REvaluate["fn <- function(max){sum(sin(1:max))}"]]

and then,

ParallelTable[RLink`RFunction["fn"][i],{i,500000,501000}]//Short//AbsoluteTiming

(* {13.027344,{{1.90482},<<999>>,{1.19949}}}  *)

while for a single core, we get:

Needs["RLink`"]
InstallR[]
REvaluate["fn <- function(max){sum(sin(1:max))}"]

and then

Table[RLink`RFunction["fn"][i],{i,500000,501000}]//Short//AbsoluteTiming

(* {57.647461,{{1.90482},<<999>>,{1.19949}}} *)

The more computationally intensive is a single call to R functions, the more you will see the speed benefit of parallelization. Since R is vectorized and also based on immutable expressions, it should be relatively easy to write R functions is a way which would be easy to parallelize and use with parallel Mathematica functionality.

Comments

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