| PE {taskPR} | R Documentation |
Attempts to execute the given expression through the parallel engine.
PE(x, global=FALSE)
x |
expression to execute in background/parallel |
global |
should this command be executed globally? |
The parallel engine takes the given expression and tries to execute it on a worker process (which may be on a remote system). It will be executed in the background and possibly in parallel with other PE calls.
Only a limited number of jobs can be run through the parallel engine at once. If that number is exceeded, then the PE call will block until some of the jobs have finished.
The given expression must be of the form "out <- f(...)".
When code{global} is true, the command is executed globally. This does several things. First, the parallel engine will wait until all workers are free before started to execute the command. Second, the command will be executed on all worker processes simultaneously. Third, the output of the command will NOT be deleted from the worker processes' workspaces (as is usually done). This "global execute" functionality is designed for loading libraries or defining functions, and not for the parallel execution of common commands.
StartPE For enabling the parallel engine.
POBJ For returning background jobs to the main process.
## Not run: # If you have MPI running StartPE(2) x = matrix(rnorm(128 * 128), 128, 128) PE( a <- svd(x) ) PE( b <- solve(x) ) PE( y <- b %*% a$u ) POBJ( y ) str(y) StopPE() ## End(Not run)