'''
進(jìn)程：資源單位
線程：執(zhí)行單位
線程才是真正干活的人，干活中需要的資源由線程所在進(jìn)程提供
每個(gè)進(jìn)程肯定自帶一個(gè)線程
每個(gè)進(jìn)程內(nèi)可創(chuàng)建多個(gè)線程
'''
'''
開進(jìn)程：
    申請(qǐng)空間
    拷貝代碼
    消耗資源大
開線程：
    同一個(gè)進(jìn)程內(nèi)創(chuàng)建多個(gè)線程，無需上述兩種操作，消耗資源相對(duì)較小
'''

from threading import Thread
import time
# 方法一
def task(name):
    print('%s is running' % name)
    time.sleep(1)
    print('%s is over' % name)
# 開啟線程不需要在main下面執(zhí)行代碼，直接書寫就可以
# 但是習(xí)慣性的將啟動(dòng)命令寫在main下面
t = Thread(target=task, args=('egon',))
t.start()  # 創(chuàng)建線程的開銷非常小，幾乎是代碼一執(zhí)行就已經(jīng)創(chuàng)建了
print('主')
'''

from threading import Thread
class MyThread(Thread):
    def __init__(self, name):
        # 重寫了別人的方法，又不知道別人的方法里有啥，就調(diào)用父類的方法
        super().__init__()
        self.name = name
    def run(self):
        print('%s is running' % self.name)
        time.sleep(1)
        print('%s is over' % self.name)
if __name__ == '__main__':
    t = MyThread('egon')
    t.start()
    print('主')
'''

from threading import Thread
def task(name):
    print('%s is running' % name)
    time.sleep(1)
    print('%s is over' % name)
if __name__ == '__main__':
    t=Thread(target=task,args=('egon',))
    t.start()
    t.join()# 主線程等待子線程運(yùn)行結(jié)束后再執(zhí)行
    print('主')

from threading import Thread
money=100
def task():
    global money
    money=66
if __name__ == '__main__':
    t=Thread(target=task,args=())
    t.start()
    print(money)

from threading import Thread
import os,time
def task():
    print('子 pid:',os.getpid())
if __name__ == '__main__':
    t=Thread(target=task,args=())
    t.start()
    print('主 pid:',os.getpid())
    # 兩個(gè)線程的pid號(hào)一樣，說明在同一個(gè)進(jìn)程下

# 這是個(gè)容易混淆的案例
from threading import Thread,current_thread,active_count
import os,time
def task(n):
    print('子',current_thread().name)
    time.sleep(n) # 延長線程存活時(shí)間
if __name__ == '__main__':
    t=Thread(target=task,args=(1,))
    t1=Thread(target=task,args=(1,))
    t.start()
    t1.start()
    t.join()
    # print('主',current_thread().name)# 獲取線程名字
    print(active_count()) # 統(tǒng)計(jì)當(dāng)前活躍的進(jìn)程數(shù)

from threading import Thread
import time
def task(name):
    print('%s is running'%name)
    time.sleep(1)
    print('%s is over'%name)
if __name__ == '__main__':
    t=Thread(target=task,args=('egon',))
    t.daemon=True #將t設(shè)置為守護(hù)線程
    t.start()
    print('主')

# 稍微有點(diǎn)迷惑性的例子
from threading import Thread
import time
def foo():
    print('1234')
    time.sleep(1)
    print('end1234')
def func():
    print('5678')
    time.sleep(3)
    print('end5678')
if __name__ == '__main__':
    t1=Thread(target=foo,args=())
    t2=Thread(target=func,args=())
    t1.daemon=True # t1設(shè)為守護(hù)線程，t2為非守護(hù)線程
    t1.start()
    t2.start()
    print('主......')

from threading import  Thread,Lock
import time
money=100
mutex=Lock()
def task():
    global money
    mutex.acquire()
    tmp=money
    time.sleep(0.1)# 模擬網(wǎng)絡(luò)延遲
    money=tmp-1
    mutex.release()
if __name__ == '__main__':
    t_list=[]
    for i in range(100):
        t=Thread(target=task,args=())
        t.start()
        t_list.append(t)
    for t in t_list:
        t.join()
    print(money)

# GTL-全局解釋器
# 重點(diǎn)：1、GIL不是python的特點(diǎn)而是Cpython解釋器的特點(diǎn)
#      2、GIL是保證解釋器級(jí)別的數(shù)據(jù)的安全
#      3、GIL會(huì)導(dǎo)致同一個(gè)進(jìn)程下的多個(gè)線程無法同時(shí)進(jìn)行（即無法利用多核優(yōu)勢(shì)）
#      4、針對(duì)不同的數(shù)據(jù)還是需要加不同的鎖處理
#      5、解釋型語言的通病，同一個(gè)進(jìn)程下多個(gè)線程無法利用多核優(yōu)勢(shì)

# 計(jì)算密集型（CPU一直工作，也沒有IO）（更適合多進(jìn)程）
from multiprocessing import Process
from threading import Thread
import os,time
# 多進(jìn)程情況
def work():
    res=0
    for i in range(0,10000000):
        res*=i
if __name__ == '__main__':
    l=[]
    print(os.cpu_count())# 獲取當(dāng)前計(jì)算機(jī)CPU核數(shù)
    start_time=time.time()
    for i in range(8):# 我計(jì)算機(jī)是8核
        p= Process(target=work,args=())
        p.start()
        l.append(p)
    for p in l:
        p.join()
    print(time.time()-start_time)

# 多線程情況
from multiprocessing import Process
from threading import Thread
import os,time
def work():
    res=0
    for i in range(0,10000000):
        res*=i
if __name__ == '__main__':
    l=[]
    print(os.cpu_count())# 獲取當(dāng)前計(jì)算機(jī)CPU核數(shù)
    start_time=time.time()
    for i in range(8):# 我計(jì)算機(jī)是8核
        t=Thread(target=work,args=())
        t.start()
        l.append(t)
    for p in l:
        p.join()
    print(time.time()-start_time)

# IO密集型（任務(wù)一直有IO）(多線程更合適)
from multiprocessing import Process
from threading import Thread
import os,time
# 多線程
def work():
    time.sleep(1)
if __name__ == '__main__':
    l=[]
    start_time=time.time()
    for i in range(40):
        t=Thread(target=work,args=())
        t.start()
        l.append(t)
    for p in l:
        p.join()
    print(time.time()-start_time)
# 運(yùn)行結(jié)果：1.0205152034759521
# 多進(jìn)程
from multiprocessing import Process
from threading import Thread
import os,time
def work():
    time.sleep(1)
if __name__ == '__main__':
    l=[]
    start_time=time.time()
    for i in range(40):
        p= Process(target=work,args=())
        # t=Thread(target=work,args=())
        # t.start()
        # l.append(t)
        p.start()
        l.append(p)
    for p in l:
        p.join()
    print(time.time()-start_time)