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01 進(jìn)程間通信

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""" 隊(duì)列:先進(jìn)先出 堆棧:先進(jìn)后出 """ from multiprocessing import Queue q = Queue(5) # 括號內(nèi)可以傳參數(shù) 表示的是這個(gè)隊(duì)列的最大存儲(chǔ)數(shù) # 往隊(duì)列中添加數(shù)據(jù) q.put(1) q.put(2) print(q.full()) # 判斷隊(duì)列是否滿了 q.put(3) q.put(4) q.put(5) print(q.full()) # q.put(6) # 當(dāng)隊(duì)列滿了之后 再放入數(shù)據(jù) 不會(huì)報(bào)錯(cuò) 會(huì)原地等待 直到隊(duì)列中有數(shù)據(jù)被取走(阻塞態(tài))print(q.get()) print(q.get()) print(q.get()) print(q.empty()) # 判斷隊(duì)列中的數(shù)據(jù)是否取完 print(q.get()) print(q.get()) print(q.empty()) print(q.get_nowait()) # 取值 沒有值不等待直接報(bào)錯(cuò) # print(q.get()) # 當(dāng)隊(duì)列中的數(shù)據(jù)被取完之后 再次獲取 程序會(huì)阻塞 直到有人往隊(duì)列中放入值 """ full get_nowait empty 都不適用于多進(jìn)程的情況 """

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02 進(jìn)程間通信IPC機(jī)制

from multiprocessing import Queue, Processdef produce(q):q.put('hello,baby~')def consumer(q):print(q.get())if __name__ == '__main__':q = Queue()p = Process(target=produce, args=(q,)) # target(把...作為目標(biāo))c = Process(target=consumer, args=(q,))p.start()c.start()

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03 生產(chǎn)者消費(fèi)者模型

""" 生產(chǎn)者:生產(chǎn)/制造數(shù)據(jù)的 消費(fèi)者:消費(fèi)/處理數(shù)據(jù)的 例子:做包子的,買包子的1.做包子遠(yuǎn)比買包子的多2.做包子的遠(yuǎn)比包子的少供需不平衡的問題 """# # multiprocessing:多重處理from multiprocessing import Process, Queue, JoinableQueue import time import randomdef producer(name, food, q):for i in range(1, 10):data = f"{name}做了第{i}份{food}"time.sleep(random.random()) # 隨機(jī)睡1秒之內(nèi) q.put(data)print(data)def consumer(name, q):while True:data = q.get()if data == None: breakprint(f"{name}吃了{(lán)data}")time.sleep(random.random())q.task_done()if __name__ == '__main__':q = JoinableQueue()p1 = Process(target=producer, args=('jason', '饅頭', q))p2 = Process(target=producer, args=('tank', '生蠔', q))c1 = Process(target=consumer, args=('ryan', q))c2 = Process(target=consumer, args=('ami', q))p1.start()p2.start()c1.daemon = Truec2.daemon = Truec1.start()c2.start()p1.join()p2.join()q.join() # 等隊(duì)列中數(shù)據(jù)全部取出

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04 線程

什么是線程進(jìn)程線程其實(shí)都是虛擬單位,都是用來幫助我們形象的描述某種事物進(jìn)程:資源單位線程:執(zhí)行單位將內(nèi)存比如成工廠那么進(jìn)程就相當(dāng)于是工廠里面的車間而你的線程就相當(dāng)于是車間里面的流水線ps:每個(gè)進(jìn)程都自帶一個(gè)線程,線程才是真正的執(zhí)行單位,進(jìn)程只是在線程運(yùn)行過程中提供代碼運(yùn)行所需要的資源為什么要有線程開進(jìn)程1.申請內(nèi)存空間 耗資源2."拷貝代碼" 耗資源開線程一個(gè)進(jìn)程內(nèi)可以起多個(gè)線程,并且線程與線程之間數(shù)據(jù)是共享的ps:開啟線程的開銷要遠(yuǎn)遠(yuǎn)小于開啟進(jìn)程的開銷如何使用線程

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05 創(chuàng)建線程的兩種方式

import time from threading import Threaddef run(name):print(f"{name} is running.")time.sleep(2)print(f"{name} is stop.")t = Thread(target=run, args=('ryan',)) # TypeError: run() takes 1 positional argument but 4 were given t.start()

import time from threading import Threadclass MyThread(Thread):def __init__(self, name):super().__init__()self.name = namedef run(self):print(f"{self.name} is running.")time.sleep(2)print(f"{self.name} is over.")t = MyThread('ryan') t.start() print('主')

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06 線程對象及其他方法

# 查看線程的活躍數(shù) import os import time from threading import Thread, active_count, current_threaddef task(name, i):print(f"{name} is running")print("主current_thread", current_thread().name)print(os.getpid())time.sleep(i)print(f"{name} is over")t1 = Thread(target=task, args=('ryan', 1)) t2 = Thread(target=task, args=('ryan', 2)) t1.start() t2.start() t2.join() print("當(dāng)前活躍線程數(shù)", active_count()) print('主') print("主current_thread", current_thread().name) print(os.getpid())

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07 守護(hù)線程

import time from threading import Thread,current_threaddef task(i):print(current_thread().name)time.sleep(i)t = Thread(target=task, args=(1,))t.daemon = True t.start() print('主')

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08 線程間通信

from threading import Threadmoney = 666def task():global moneymoney = 999t = Thread(target=task) t.start() t.join() print(money)

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09 互斥鎖

from threading import Thread, Lock import timen = 100def task(mutex):global nmutex.acquire() # 獲得tmp = ntime.sleep(0.1)n = tmp - 1mutex.release()t_list = [] mutex = Lock() for i in range(100):t = Thread(target=task, args=(mutex,))t.start()t_list.append(t) for t in t_list:t.join() print(n)

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10 小例子

from threading import Thread from multiprocessing import Process import time def foo():print(123)time.sleep(1)print("end123")def bar():print(456)time.sleep(3)print("end456")if __name__ == '__main__':t1=Thread(target=foo)t2=Thread(target=bar)t1.daemon=Truet1.start()t2.start()print("main-------")

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轉(zhuǎn)載于:https://www.cnblogs.com/Ryan-Yuan/p/11343434.html

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