subscribeon.swift

//: Playground - noun: a place where people can play

import UIKit
import RxSwift
import RxCocoa

let ps = PublishSubject<Int>()

func pt() -> String {
    let thread = NSThread.currentThread()
    let main = thread.isMainThread ? "[Main] " : ""
    let qos = currentThreadQos()
    let tid = pthread_mach_thread_np(pthread_self())
    return "[\(tid)] \(main)\(qos)"
}

ps
    .subscribeOn(ConcurrentDispatchQueueScheduler(globalConcurrentQueueQOS: .UserInitiated))
    .map {
        print("map \(pt()) \($0)")
        return $0
    }
    //.observeOn(ConcurrentDispatchQueueScheduler(globalConcurrentQueueQOS: .Utility))
    .subscribeNext { (i: Int) in
        print("subscribe \(pt()) \(i)")
    }

ps.onNext(0)
ps.onNext(1)
ps.onNext(2)