Worker Pools in OpenSCAD

In this example, we’ll look at how to implement a worker pool using OpenSCAD’s modules and recursion. OpenSCAD doesn’t have built-in concurrency or threading, so we’ll simulate the concept of worker pools using a different approach.

// Simulating a worker function
module worker(id, job) {
    echo(str("worker ", id, " started job ", job));
    // Simulate work by doing nothing
    echo(str("worker ", id, " finished job ", job));
}

// Simulating a pool of workers
module worker_pool(workers, jobs, current_worker = 0, current_job = 0) {
    if (current_job < len(jobs)) {
        worker(current_worker + 1, jobs[current_job]);
        worker_pool(workers, jobs, (current_worker + 1) % workers, current_job + 1);
    }
}

// Main function
module main() {
    num_workers = 3;
    jobs = [1, 2, 3, 4, 5];
    
    echo("Starting worker pool");
    worker_pool(num_workers, jobs);
    echo("All jobs completed");
}

main();

In this OpenSCAD implementation:

1. We define a worker module that simulates a worker. It takes an id and a job as parameters and echoes messages about starting and finishing the job.

2. The worker_pool module simulates the pool of workers. It uses recursion to distribute jobs among workers. The current_worker parameter keeps track of which worker should handle the next job, and current_job keeps track of the job index.

3. In the main module, we define the number of workers and the jobs to be done. Then we call the worker_pool module to start the simulation.

4. Finally, we call main() to execute the program.

To run the program, save it as worker_pools.scad and open it with OpenSCAD. The console output will show the simulated worker pool in action.

When you run this script, you’ll see output similar to this in the OpenSCAD console:

ECHO: "Starting worker pool"
ECHO: "worker 1 started job 1"
ECHO: "worker 1 finished job 1"
ECHO: "worker 2 started job 2"
ECHO: "worker 2 finished job 2"
ECHO: "worker 3 started job 3"
ECHO: "worker 3 finished job 3"
ECHO: "worker 1 started job 4"
ECHO: "worker 1 finished job 4"
ECHO: "worker 2 started job 5"
ECHO: "worker 2 finished job 5"
ECHO: "All jobs completed"

This simulation demonstrates the concept of a worker pool, where multiple workers (in this case, 3) handle a series of jobs. However, it’s important to note that this is not truly concurrent or parallel execution, as OpenSCAD doesn’t support multi-threading. Instead, it’s a sequential simulation of how a worker pool might operate.

In real-world scenarios with languages that support true concurrency, worker pools can significantly improve performance for certain types of tasks by distributing work across multiple threads or processes.