Waitgroups in Wolfram Language

In Wolfram Language, we can use ParallelDo to execute tasks concurrently and WaitAll to wait for all tasks to complete. This is similar to the concept of WaitGroups in other languages.

(* Import necessary packages *)
Needs["Parallel`"]

(* Define the worker function *)
worker[id_] := Module[{},
  Print["Worker ", id, " starting"];
  (* Pause to simulate an expensive task *)
  Pause[1];
  Print["Worker ", id, " done"];
]

(* Main function *)
main[] := Module[{tasks},
  (* Launch several parallel tasks *)
  tasks = Table[
    ParallelSubmit[worker[i]],
    {i, 1, 5}
  ];
  
  (* Wait for all tasks to complete *)
  WaitAll[tasks];
]

(* Run the main function *)
main[]

In this example:

1. We import the Parallel package, which provides functions for parallel computing.

2. The worker function simulates a task that takes some time to complete. It prints a message when starting and finishing.

3. In the main function:

   • We use Table with ParallelSubmit to launch several tasks concurrently.
   • Each task is an invocation of the worker function with a unique ID.
   • WaitAll is used to block until all tasks have completed.

4. Finally, we call the main function to execute our parallel tasks.

When you run this code, you’ll see output similar to:

Worker 3 starting
Worker 1 starting
Worker 2 starting
Worker 4 starting
Worker 5 starting
Worker 3 done
Worker 1 done
Worker 2 done
Worker 4 done
Worker 5 done

Note that the order of workers starting and finishing may vary between executions due to the nature of parallel execution.

While this approach doesn’t provide a direct equivalent to Go’s WaitGroups, it achieves a similar result of running multiple tasks concurrently and waiting for their completion. Wolfram Language’s parallel computing functions handle the underlying synchronization automatically.

For more advanced use cases involving error handling in parallel computations, you can explore functions like CheckAbort or use pattern matching on the results returned by WaitAll.