Multicore

A single instance of Slimane runs in a single thread. To take advantage of multi-core systems the user will sometimes want to launch a cluster of Slimane processes to handle the load.

Cluster Mode

A Master and Worker Pattern Example.

The request(handle) that came to master is send to worker via ipc. The worker is determined with simple round robin algorithm.

// For Cluster app
if Cluster.isMaster {
    for _ in 0..<OS.cpus().count {
        let worker = try! Cluster.fork(silent: false)
    }

    try! Slimane().listen()
} else {
    let app = Slimane()
    app.get("/") { request, response, responder in
        var response = response
        response.text("Hello! process id is \(Process.pid)")
        responder(.respond(response))
    }

    try! app.listen()
}

IPC

IPC between Master and Worker Processes

On Master

var worker = try! Cluster.fork(silent: false)

// Send message to the worker
worker.send(.Message("message from master"))

// Receive event from the worker
worker.onEvent { event in
    if case .message(let str) = event {
        print(str)
    }

    else if case .online = event {
        print("Worker: \(worker.id) is online")
    }

    else if case .exit(let status) = event {
        print("Worker: \(worker.id) is dead. status: \(status)")
        let worker = try! Cluster.fork(silent: false)
        observeWorker(worker)
    }
}

On Worker

// Receive event from the master
Process.onEvent { event in
    if case .message(let str) = event {
        print(str)
    }
}

// Send message to the master
Process.send(.message("Hey!"))