alias uint8  = ubyte;

import std.stdio;
//import std.parallelism : defaultPoolThreads;
import std.concurrency : receive, receiveOnly, receiveTimeout, send, spawn, thisTid, Tid, ThreadScheduler, FiberScheduler;
import core.time : Duration, dur;
import core.thread : Thread;


//void test1_worker(uint8 n){
void test1_worker(int n){
  writeln("started worker = ", n);
  
  Thread.sleep(dur!"seconds"(120));
  
  writeln("stopped worker = ", n);
}


void test1_spawner(){
  //uint8 i = 10; // 10 = 1.8 Mb RAM // 255 = 2.9 Mb RAM // 1000 = 6.1 Mb RAM // 10_000 = 47.9 Mb RAM // 100_000 = 180.3 -> 434.4 Mb RAM ,, 161.8 -> 607.7 Mb RAM
  int i = 100_000; // freeze with 180.3 -> 434.4 Mb RAM .. (( 161.8 -> 607.7 Mb RAM
  //int i = 1_000;
  
  auto scheduler = new ThreadScheduler();
  //auto scheduler = new FiberScheduler;
  
  //scheduler.start({});
  
  while(i > 0){
    scheduler.spawn({
      writeln("thread ", thisTid(), " == i = ", i);
      //Thread.sleep(dur!"seconds"(3));
      Thread.sleep(dur!"seconds"(120));
    });
    i--;
  }
  
  
  /*
  //while(i > 0){ // 10 CPU' cores ?
  foreach(i2; 0..10){ // 10 CPU' cores ?
    //auto i2 = i;
    scheduler.spawn({
      foreach(j; 0..10){ // 10 threads per CPU core ?
        writeln("thread ", thisTid(), " == i, j = ", i2, " ", j);
        Thread.sleep(dur!"seconds"(3));
        //Thread.sleep(dur!"seconds"(120));
      }
    });
    //i--;
  }
  */
  
  /*
  while(i > 0){
    spawn(&test1_worker, i);
    
    i--;
  }
  */
  
}


/*
// 10 threads (10 OS processes ?) - but with problem for 100_000 threads - but only on one CPU core (

> make run
./vtest2
started worker = 8
started worker = 7
started worker = 9
started worker = 6
started worker = 1
started worker = 10
started worker = 5
started worker = 3
started worker = 2
started worker = 4
stopped worker = 8
stopped worker = 9
stopped worker = 7
stopped worker = 10
stopped worker = 6
stopped worker = 1
stopped worker = 4
stopped worker = 3
stopped worker = 5
stopped worker = 2
hello here!

*/