startLocalWorkers: Start one or more background R worker processes on the local...
In bwlewis/doRedis: 'Foreach' Parallel Adapter Using the 'Redis' Database

Description Usage Arguments Details Value See Also Examples

Use startLocalWorkers to start one or more doRedis R worker processes in the background. The worker processes are started on the local system using the redisWorker function.

startLocalWorkers(
  n,
  queue,
  host = "localhost",
  port = 6379,
  iter = Inf,
  linger = 30,
  log = stdout(),
  Rbin = paste(R.home(component = "bin"), "R", sep = "/"),
  password,
  ...
)

`n`	number of workers to start
`queue`	work queue name
`host`	Redis database host name or IP address
`port`	Redis database port number
`iter`	maximum number of tasks to process before exiting the worker loop
`linger`	timeout in seconds after which the work queue is deleted that the worker terminates
`log`	print messages to the specified file connection
`Rbin`	full path to the command-line R program
`password`	optional Redis database password
`...`	optional additional parameters passed to the `redisWorker` function

Running workers self-terminate after a linger period if their work queues are deleted with the removeQueue function, or when network activity with Redis remains inactive for longer than the timeout period set in the redisConnect function. That value defaults internally to 3600 (one hour) in startLocalWorkers. You can increase it by including a timeout=n argument value.

NULL is invisibly returned.

registerDoRedis, redisWorker

# Only run if a Redis server is running
if (redux::redis_available()) {
## The example assumes that a Redis server is running on the local host
## and standard port.

# Start a single local R worker process
startLocalWorkers(n=1, queue="R jobs", linger=1)

# Run a simple sampling approximation of pi:
registerDoRedis("R jobs")
print(foreach(j=1:10, .combine=sum, .multicombine=TRUE) %dopar%
        4 * sum((runif(1000000) ^ 2 + runif(1000000) ^ 2) < 1) / 10000000)

# Clean up
removeQueue("R jobs")
}