% Generated by roxygen2: do not edit by hand
% Please edit documentation in R/parallelStart.R
\name{parallelStart}
\alias{parallelStart}
\alias{parallelStartLocal}
\alias{parallelStartMulticore}
\alias{parallelStartSocket}
\alias{parallelStartMPI}
\alias{parallelStartBatchJobs}
\alias{parallelStartBatchtools}
\title{Parallelization setup for parallelMap.}
\usage{
parallelStart(mode, cpus, socket.hosts, bj.resources = list(),
  bt.resources = list(), logging, storagedir, level,
  load.balancing = FALSE, show.info, suppress.local.errors = FALSE,
  ...)

parallelStartLocal(show.info, suppress.local.errors = FALSE, ...)

parallelStartMulticore(cpus, logging, storagedir, level,
  load.balancing = FALSE, show.info, ...)

parallelStartSocket(cpus, socket.hosts, logging, storagedir, level,
  load.balancing = FALSE, show.info, ...)

parallelStartMPI(cpus, logging, storagedir, level,
  load.balancing = FALSE, show.info, ...)

parallelStartBatchJobs(bj.resources = list(), logging, storagedir, level,
  show.info, ...)

parallelStartBatchtools(bt.resources = list(), logging, storagedir,
  level, show.info, ...)
}
\arguments{
\item{mode}{[\code{character(1)}]\cr
Which parallel mode should be used:
\dQuote{local}, \dQuote{multicore}, \dQuote{socket}, \dQuote{mpi}, \dQuote{BatchJobs}.
Default is the option \code{parallelMap.default.mode} or, if not set,
\dQuote{local} without parallel execution.}

\item{cpus}{[\code{integer(1)}]\cr
Number of used cpus.
For local and BatchJobs mode this argument is ignored.
For socket mode, this is the number of processes spawned on localhost, if
you want processes on multiple machines use \code{socket.hosts}.
Default is the option \code{parallelMap.default.cpus} or, if not set,
\code{\link[parallel]{detectCores}} for multicore mode,
\code{max(1, \link[Rmpi]{mpi.universe.size} - 1)} for mpi mode
and 1 for socket mode.}

\item{socket.hosts}{[\code{character}]\cr
Only used in socket mode, otherwise ignored.
Names of hosts where parallel processes are spawned.
Default is the option \code{parallelMap.default.socket.hosts}, if this option exists.}

\item{bj.resources}{[\code{list}]\cr
Resources like walltime for submitting jobs on HPC clusters via BatchJobs.
See \code{\link[BatchJobs]{submitJobs}}.
Defaults are taken from your BatchJobs config file.}

\item{bt.resources}{[\code{list}]\cr
Analog to \code{bj.resources}.
See \code{\link[batchtools]{submitJobs}}.}

\item{logging}{[\code{logical(1)}]\cr
Should slave output be logged to files via \code{\link{sink}} under the \code{storagedir}?
Files are named "<iteration_number>.log" and put into unique
subdirectories named \dQuote{parallelMap_log_<nr>} for each subsequent
\code{\link{parallelMap}} operation.
Previous logging directories are removed on \code{parallelStart}
if \code{logging} is enabled.
Logging is not supported for local mode, because you will see all
output on the master and can also run stuff like
\code{\link{traceback}} in case of errors.
Default is the option \code{parallelMap.default.logging} or, if not set,
\code{FALSE}.}

\item{storagedir}{[\code{character(1)}]\cr
Existing directory where log files and intermediate objects for BatchJobs
mode are stored.
Note that all nodes must have write access to exactly this path.
Default is the current working directory.}

\item{level}{[\code{character(1)}]\cr
You can set this so only calls to \code{\link{parallelMap}} that have exactly the same level are parallelized.
Default is the option \code{parallelMap.default.level} or, if not set,
\code{NA} which means all calls to \code{\link{parallelMap}} are are potentially parallelized.}

\item{load.balancing}{[\code{logical(1)}]\cr
Enables load balancing for multicore, socket and mpi.
Set this to \code{TRUE} if you have heterogeneous runtimes.
Default is \code{FALSE}}

\item{show.info}{[\code{logical(1)}]\cr
Verbose output on console for all further package calls?
Default is the option \code{parallelMap.default.show.info} or, if not set,
\code{TRUE}.}

\item{suppress.local.errors}{[\code{logical(1)}]\cr
Should reporting of error messages during function evaluations in local mode be suppressed?
Default ist FALSE, i.e. every error message is shown.}

\item{...}{[any]\cr
Optional parameters, for socket mode passed to \code{\link[parallel]{makePSOCKcluster}},
for mpi mode passed to \code{\link[parallel]{makeCluster}} and for multicore
passed to \code{\link[parallel]{mcmapply}} (\code{mc.preschedule} (overwriting \code{load.balancing}),
\code{mc.set.seed},
\code{mc.silent} and \code{mc.cleanup} are supported for multicore).}
}
\value{
Nothing.
}
\description{
Defines the underlying parallelization mode for \code{\link{parallelMap}}.
Also allows to set a \dQuote{level} of parallelization.
Only calls to \code{\link{parallelMap}} with a matching level are parallelized.
The defaults of all settings are taken from your options, which you can
also define in your R profile.
For an introductory tutorial and information on the options configuration, please
go to the project's github page at \url{https://github.com/berndbischl/parallelMap}.
}
\details{
Currently the following modes are supported, which internally dispatch the mapping operation
to functions from different parallelization packages:

\describe{
\item{local}{No parallelization with \code{\link{mapply}}.}
\item{multicore}{Multicore execution on a single machine with \code{\link[parallel]{mclapply}}.}
\item{mpi}{Snow MPI cluster on one or multiple machines with \code{\link[parallel]{makeCluster}} and \code{\link[parallel]{clusterMap}}.}
\item{BatchJobs}{Parallelization on batch queuing HPC clusters, e.g., Torque, SLURM, etc., with \code{\link[BatchJobs]{batchMap}}.}
}

For BatchJobs mode you need to define a storage directory through the argument \code{storagedir} or
the option \code{parallelMap.default.storagedir}.
}
