A remote future is a future that uses remote cluster evaluation, which means that its value is computed and resolved remotely in another process.
transparent(...)remote(
...,
workers = NULL,
revtunnel = TRUE,
myip = NULL,
persistent = TRUE,
homogeneous = TRUE,
envir = parent.frame()
)
A ClusterFuture.
Additional named elements passed to Future()
.
A cluster
object,
a character vector of host names, a positive numeric scalar,
or a function.
If a character vector or a numeric scalar, a cluster
object
is created using makeClusterPSOCK(workers)
.
If a function, it is called without arguments when the future
is created and its value is used to configure the workers.
The function should return any of the above types.
If TRUE, reverse SSH tunneling is used for the PSOCK cluster nodes to connect back to the master R process. This avoids the hassle of firewalls, port forwarding and having to know the internal / public IP address of the master R session.
The external IP address of this machine. If NULL, then it is inferred using an online service (default).
If FALSE, the evaluation environment is cleared from objects prior to the evaluation of the future.
If TRUE, all cluster nodes is assumed to use the
same path to Rscript
as the main R session. If FALSE, the
it is assumed to be on the PATH for each node.
If NULL, then parallelly::makeClusterPSOCK()
will decide on TRUE
or FALSE depending on workers
.
The environment from where global objects should be identified.
The remote
plan is a very similar to the cluster
plan, but provides
more convenient default argument values when connecting to remote machines.
Specifically, remote
uses persistent = TRUE
by default, and it sets
homogeneous
, revtunnel
, and myip
"wisely" depending on the value of
workers
.
' See below for example on how remote
and cluster
are related.
This function is not meant to be called directly. Instead, the typical usages are:
# Evaluate futures on remote machine 'server.example.org', and
# any nested ones sequentially (default) on that remote machine
plan(remote, workers = "server.example.org")# Evaluate futures on remote machine 'server.example.org', and
# nested ones in parallel on that remote machine
plan(list(
tweak(remote, workers = "server.example.org"),
multisession
))
# Evaluate futures on remote machine 'server.example.org', and
# nested ones in parallel on the remote machines n1, n2, and n3.
plan(list(
tweak(remote, workers = "server.example.org"),
tweak(cluster, workers = c("n1", "n2", "n3"))
))