rrq_worker_spawn: Spawn a worker

In mrc-ide/rrq: Simple Redis Queue

Spawn a worker

Description

Spawn a worker in the background

Usage

rrq_worker_spawn(
  n = 1,
  logdir = NULL,
  timeout = 600,
  name_config = "localhost",
  worker_id_base = NULL,
  time_poll = 0.2,
  progress = NULL,
  controller = NULL,
  offload_path = NULL
)

Arguments

n	Number of workers to spawn
logdir	Path of a log directory to write the worker process log to, interpreted relative to the current working directory
timeout	Time to wait for workers to appear. If 0 then we don't wait for workers to appear (you can run the wait_alive method of the returned object to run this test manually)
name_config	Name of the configuration to use. By default the "localhost" configuration is used
worker_id_base	Optional base to construct the worker ids from. If omitted a random base will be used. Actual ids will be created but appending integers to this base.
time_poll	Polling period (in seconds) while waiting for workers to come up.
progress	Show a progress bar while waiting for workers (when timeout is at least 0)
controller	The controller to use. If not given (or NULL) we'll use the controller registered with rrq_default_controller_set().
offload_path	The path to create an offload store at. See rrq_controller for details.

Details

Spawning multiple workers. If n is greater than one, multiple workers will be spawned. This happens in parallel so it does not take n times longer than spawning a single worker.

Beware that signals like Ctrl-C passed to this R instance can still propagate to the child processes and can result in them dying unexpectedly. It is probably safer to start processes in a completely separate session.

Value

An rrq_worker_manager object with fields:

• id: the ids of the spawned workers

• wait_alive: a method to wait for workers to come alive

• stop: a method to stop workers

• kill: a method to kill workers abruptly by sending a signal

• is_alive: a method that checks if a worker is currently alive

• logs: a method that returns logs for a single worker

All the methods accept a vector of worker names, or integers, except logs which requires a single worker id (as a string or integer). For all methods except logs, the default of NULL means "all managed workers".

mrc-ide/rrq documentation built on Nov. 28, 2024, 1:12 p.m.