线程与线程池

threading.currentThread()　　返回当前的线程变量
threading.enumerate()　　　　返回一个包含正在运行的线程的list,正在运行指线程启动后,结束前,不包括启动前和终止后的线程
threading.activeCount()　　　返回正在运行的线程数量,与len(threading.enumerate()有相同的结果)

import threading
import time
from threading import Thread,current_thread
 
def f1(n):
    time.sleep(1)
    print(‘子线程名称‘, current_thread().getName()) #Thread-1
    print(‘%s号线程任务‘%n)
 
 
if __name__ == ‘__main__‘:
    t1 = Thread(target=f1,args=(1,))
    t1.start()
    print(‘主线程名称‘,current_thread().getName()) #MainThread
    print(‘主线程ID‘,current_thread().ident)
    print(current_thread())
    print(threading.enumerate()) #[<_MainThread(MainThread, started 6708)>, <Thread(Thread-1, started 7848)>]
    print(threading.active_count())
    # print(‘主线程‘)

共有三种基本用法:Queue,LifoQueue,PriorityQueue
一:先进先出队列
q = queue.Queue(3)  #先进先出 fifo first in first out
q.put(1)
q.put(2)
# print(‘当前队列内容长度‘,q.qsize())
q.put(3)
print(‘查看队列是否满了‘,q.full())
try:
    q.put_nowait(4)  # 报错queue.Full
except Exception:
    print(‘队列满了‘)
print(q.get())
print(q.get())
print(‘查看队列是否为空‘,q.empty())
print(q.get())
print(‘查看队列是否为空‘,q.empty())
try:
    q.get_nowait()  # queue.Empty
except Exception:
    print(‘队列空了‘)

二 先进后出队列,或者后进先出,类似于栈
q = queue.LifoQueue(3)
 
q.put(1)
q.put(2)
q.put(3)
 
print(q.get())
print(q.get())
print(q.get())

三，优先级队列
q = queue.PriorityQueue(5)
# q.put((5,‘glex‘))
q.put((5,(2,3)))  #如果说值里面的元素是数字类型,那么当两个值的优先级相同时,比较的是两个值的大小,小的优先被取出来
　　　　　　　　　　 #如果元素是字符串,那么依次比较每个字母的ascii表中的位置,小的优先被取出来
q.put((5,(2,2,3)))
q.put((2,‘zasdf‘))
q.put((-1,‘yadsf‘))
q.put((2,{‘k‘:666})) #如果优先级数字相同,如果数据类型不同会报错
q.put((2,(‘a‘,‘b‘)))
q.put((1,(1,2)))
q.put((3,(1,2)))
q.put((-10,(1,2)))
print(q.get())
print(q.get())
print(q.get())

1.使用multiprocessing模块创建
from threading import Thread
thread_pool = ThreadPoolManger(4)

使用concurrent.futures模块创建
将进程池和线程池放到一起,统一使用方式，使用threadPollExecutor和ProcessPollExecutor的方式一样，而且只要通过这个concurrent.futures导入就可以直接用他们两个了
p = ThreadPoolExecutor(4)  # 默认个数是 cpu的个数*5
p = ProcessPoolExecutor(4) # 默认个数是cpu的核数

import time
from threading import current_thread
from concurrent.futures import ThreadPoolExecutor,ProcessPoolExecutor
 
def f1(n,s):
    time.sleep(1)
    # print(‘%s号子线程‘%current_thread().ident)
    # print(n,s)
    return
 
if __name__ == ‘__main__‘:
 
    tp = ThreadPoolExecutor(4)
    # tp = ProcessPoolExecutor(4)
    # tp.map(f1,range(10))  #异步提交任务,参数同样是任务名称,可迭代对象
    res_list = []
    for i in range(10):
        res = tp.submit(f1,i,‘baobao‘)  #submit是给线程池异步提交任务,
        print(res)
        # res.result()
        res_list.append(res)
 
    # for r in res_list:
    #     print(r.result())
 
    tp.shutdown()  #主线程等待所有提交给线程池的任务,全部执行完毕 close + join
    for r in res_list:
        print(r.result())
    print(‘主线程结束‘)