thread:concurrent

swipl
- library

concurrent_forall(:Generate, :Action) is semidet

concurrent_forall(:Generate, :Action, +Options) is semidet

True when Action is true for all solutions of Generate. This has the same semantics as forall/2, but the Action goals are executed in multiple threads. Notable a failing Action or a Action throwing an exception signals the calling thread which in turn aborts all workers and fails or re-throws the generated error. Options:

threads(+Count): Number of threads to use. The default is determined by the Prolog flag cpu_count.

To be done: - Ideally we would grow the set of workers dynamically, similar to dynamic scheduling of HTTP worker threads. This would avoid creating threads that are never used if Generate is too slow or does not provide enough answers and would further raise the number of threads if Action is I/O bound rather than CPU bound.