线程,线程池|进程，进程池

Posted 2020-09-11

线程

import threading

 

锁

 

lock=threading.Lock() #

lock=threading.RLock() #递归锁，多层锁定，多层解锁

lock.acquire()

lock.release()

import threading
import time
v = 10
#lock = threading.Lock() # 只能开一把
lock = threading.RLock()# 可以开多把

def task(arg):
    time.sleep(2)
    # 申请使用锁，其他人等
    lock.acquire()
    lock.acquire()
    global v
    v -= 1
    print(v)
    # 释放
    lock.release()
    lock.release()

for i in range(10):
    t = threading.Thread(target=task,args=(i,))
    t.start()

View Code

 

多个人使用锁

lock = threading.BoundedSemaphore(3)
lock.acquire()

lock.release()

import threading
import time
lock = threading.BoundedSemaphore(3)

def task(arg):
    # 申请使用锁，其他人等
    lock.acquire()
    time.sleep(1)
    global v
    v -= 1
    print(v)
    # 释放
    lock.release()

for i in range(10):
    t = threading.Thread(target=task,args=(i,))
    t.start()

View Code

 

事件（锁，所有锁的释放与锁定）

lock = threading.Event()

lock.wait()

lock.clear()

import threading
import time
lock = threading.Event()

def task(arg):
    time.sleep(1)
    # 锁住所有的线程
    lock.wait()
    # 申请使用锁，其他人等
    print(arg)


for i in range(10):
    t = threading.Thread(target=task,args=(i,))
    t.start()
while True:
    value = input(‘>>>>‘)
    if value == ‘1‘:
        lock.set()
        lock.clear()

View Code

 

指定释放几个线程锁

lock = threading.Condition()

 

import threading
import time
lock = threading.Condition()

def task(arg):
    time.sleep(1)
    # 锁住所有的线程
    lock.acquire()
    lock.wait()
    # 申请使用锁，其他人等
    print(‘线程‘,arg)
    lock.release()


for i in range(10):
    t = threading.Thread(target=task,args=(i,))
    t.start()
while True:
    value = input(‘>>>>‘)
    lock.acquire()
    lock.notify(int(value))  #指定释放几个锁
    lock.release()

View Code

线程池

from concurrent.futures import ThreadPoolExecutor  #导入指定模块
import time
import requests

def task(url):
    response=requests.get(url)
    print("请求结果",url,len(response.content))

url_list=[
    "http://www.baidu.com",
    "http://cn.bing.com",
    "http://www.oldboyedu.com"
]
pool=ThreadPoolExecutor(2)   #创建线程池
for url in url_list:
    pool.submit(task,url)        #线程池调用

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自定义回调函数

from concurrent.futures import ThreadPoolExecutor
import time
import requests

def txt(future):
    cc=future.result()
    print(cc)
def task(url):
    response=requests.get(url)
    return(url,len(response.content))

url_list=[
    "http://www.baidu.com",
    "http://cn.bing.com",
    "http://www.oldboyedu.com"
]
pool=ThreadPoolExecutor(2)
for url in url_list:
    future=pool.submit(task,url)
    future.add_done_callback(txt)

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进程
from multiprocessing import Process #导入模块

from multiprocessing import Process
import time
def task(arg):
    time.sleep(arg)
    print(arg)

if __name__ == ‘__main__‘:
    for i in range(10):
        p = Process(target=task,args=(i,))
        p.daemon = True
        # p.daemon = False
        p.start()
        p.join(1)

    print(‘主进程最后...‘)

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进程间内存共享

1、Array

from multiprocessing import Process,Array
import time
import threading

def task(num,li):
    li[num]=1
    print(list(li))

if __name__ == ‘__main__‘:
    v = Array("i",10)
    for i in range(10):
        p = Process(target=task,args=(i,v,))
        # p = threading.Thread(target=task,args=(i,v,))
        p.start()

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2、Manager (内部socket对接连接)

Manager.list() Manager.dict()

 

from multiprocessing import Process,Manager
import time
import threading

def task(num,li):
    li.append(num)
    print(list(li))

if __name__ == ‘__main__‘:
    dic=Manager().list()
    for i in range(10):
        p = Process(target=task,args=(i,dic,))
        # p = threading.Thread(target=task,args=(i,v,))
        p.start()
        p.join()

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进程池

 

from concurrent.futures import ProcessPoolExecutor

def call(arg):
    data = arg.result()
    print(data)

def task(arg):
    print(arg)
    return arg + 100

if __name__ == ‘__main__‘:
    pool = ProcessPoolExecutor(5)
    for i in range(10):
        obj = pool.submit(task,i)
        obj.add_done_callback(call)

View Code