This function will block if all cores are occupied and
will be unblocked as soon as one of the already running
multicore futures is resolved. For the total number of
cores available including the current/main R process, see
availableCores()
.
Not all operating systems support process forking and thereby not multicore
futures. For instance, forking is not supported on Microsoft Windows.
Moreover, process forking may break some R environments such as RStudio.
Because of this, the future package disables process forking also in
such cases. See supportsMulticore()
for details.
Trying to create multicore futures on non-supported systems or when
forking is disabled will result in multicore futures falling back to
becoming sequential futures.
The preferred way to create an multicore future is not to call
this function directly, but to register it via
plan(multicore)
such that it becomes the default
mechanism for all futures. After this future()
and %<-%
will create multicore futures.