{
 "cells": [
  {
   "cell_type": "markdown",
   "id": "89cd8e00",
   "metadata": {},
   "source": [
    "## Uneven core distribution"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 17,
   "id": "1c9baac3",
   "metadata": {},
   "outputs": [],
   "source": [
    "import multiprocessing\n",
    "import time\n",
    "import os"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 20,
   "id": "8294ab61",
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      " 4182758  4182759  4182760  4182762  4182761 \n",
      "\n",
      "\n",
      "\n",
      "\n",
      " 4182759  4182761  4182760  4182762 \n",
      "\n",
      "\n",
      "\n",
      " 4182760  4182759  4182761  4182762 \n",
      "\n",
      "\n",
      "\n",
      " 4182759  4182761  4182760  4182762 \n",
      "\n",
      "\n",
      "\n",
      " 4182759  4182761  4182760  4182762 \n",
      "\n",
      "\n",
      "\n",
      " 4182759  4182761  4182760  4182762 \n",
      "\n",
      "\n",
      "\n",
      " 4182759  4182762  4182760  4182761 \n",
      "\n",
      "\n",
      "\n",
      " 4182761  4182762  4182759  4182760 \n",
      "\n",
      "\n",
      "\n",
      " 4182762  4182759  4182761  4182760 \n",
      "\n",
      "\n",
      "\n",
      " 4182761  4182759  4182762  4182760 \n",
      "\n",
      "\n",
      "\n",
      "10.0\n"
     ]
    }
   ],
   "source": [
    "def foo(x):\n",
    "    print(\" \" + str(os.getpid()) + \" \")\n",
    "    time.sleep(x)\n",
    "\n",
    "p = multiprocessing.Pool(5)\n",
    "t0 = time.time()\n",
    "out = p.map(foo, [10] + [1]*40, chunksize=1)\n",
    "print(round((time.time() - t0), 1))\n",
    "p.close()\n",
    "p.join()\n",
    "# 4 + 9"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "id": "9f07b5f3",
   "metadata": {},
   "outputs": [],
   "source": []
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "id": "6f37be32",
   "metadata": {},
   "outputs": [],
   "source": []
  },
  {
   "cell_type": "code",
   "execution_count": 14,
   "id": "c920ce3d",
   "metadata": {},
   "outputs": [],
   "source": [
    "def reader_proc(queue):\n",
    "    while True:\n",
    "        msg = queue.get()\n",
    "        if msg == \"DONE\":\n",
    "            break\n",
    "        time.sleep(msg)\n",
    "        \n",
    "n_cores = 5\n",
    "queue = multiprocessing.Queue()\n",
    "        \n",
    "all_reader_procs = []\n",
    "for n in range(0, n_cores):\n",
    "    reader_p = multiprocessing.Process(target=reader_proc, args=((queue),))\n",
    "    reader_p.daemon = True\n",
    "    reader_p.start()\n",
    "    all_reader_procs.append(reader_p)\n",
    "\n",
    "for n in [10] + [1]*40:\n",
    "    queue.put(n)\n",
    "for n in range(n_cores):\n",
    "    queue.put(\"DONE\")"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 15,
   "id": "c3b69212",
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "10.0\n"
     ]
    }
   ],
   "source": [
    "t0 = time.time()\n",
    "for idx, a_reader_proc in enumerate(all_reader_procs):\n",
    "    a_reader_proc.join()\n",
    "print(round((time.time() - t0), 1))"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "id": "10c55537",
   "metadata": {},
   "outputs": [],
   "source": []
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "id": "5e64e05c",
   "metadata": {},
   "outputs": [],
   "source": []
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "id": "518033f6",
   "metadata": {},
   "outputs": [],
   "source": []
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "id": "43ca5d74",
   "metadata": {},
   "outputs": [],
   "source": []
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "id": "1780272e",
   "metadata": {},
   "outputs": [],
   "source": []
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "id": "2d2a188a",
   "metadata": {},
   "outputs": [],
   "source": []
  }
 ],
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