在Python中使用异步Socket编程性能测试
OK,首先写一个pythonsocket的server段,对开放三个端口:10000,10001,10002.krondo的例子中是每个server绑定一个端口,测试的时候需要分别开3个shell,分别运行.这太麻烦了,就分别用三个Thread来运行这些services.
importoptparse importos importsocket importtime fromthreadingimportThread importStringIO txt='''1111 2222 3333 4444 ''' defserver(listen_socket): whileTrue: buf=StringIO.StringIO(txt) sock,addr=listen_socket.accept() print'Somebodyat%swantspoetry!'%(addr,) whileTrue: try: line=buf.readline().strip() ifnotline: sock.close() break sock.sendall(line)#thisisablockingcall print'sendbytestoclient:%s'%line #sock.close() exceptsocket.error: sock.close() break time.sleep(1)#server和client连接后,server会故意每发送一个单词后等待一秒钟后再发送另一个单词 defmain(): ports=[10000,10001,10002] forportinports: listen_socket=socket.socket(socket.AF_INET,socket.SOCK_STREAM) listen_socket.setsockopt(socket.SOL_SOCKET,socket.SO_REUSEADDR,1) addres=(str('127.0.0.1'),port) listen_socket.bind(addres) listen_socket.listen(5) print"startlistenat:%s"%(port,) worker=Thread(target=server,args=[listen_socket]) worker.setDaemon(True) worker.start() if__name__=='__main__': main() whileTrue: time.sleep(0.1)#如果不sleep的话,CPU会被Python完全占用了 pass
下面是一个client,没有才用异步网络,连接这个三个端口的server:
importsocket if__name__=='__main__': ports=[10000,10001,10002] forportinports: address=(str('127.0.0.1'),port) sock=socket.socket(socket.AF_INET,socket.SOCK_STREAM) sock.connect(address) poem='' whileTrue: data=sock.recv(4) ifnotdata: sock.close() break poem+=data printpoem
下面用异步的client来读取,代码如下:
importdatetime,errno,optparse,select,socket defconnect(port): """Connecttothegivenserverandreturnanon-blockingsocket.""" address=(str('127.0.0.1'),port) sock=socket.socket(socket.AF_INET,socket.SOCK_STREAM) sock.connect(address) sock.setblocking(0) returnsock defformat_address(address): host,port=address return'%s:%s'%(hostor'127.0.0.1',port) if__name__=='__main__': ports=[10000,10001,10002] start=datetime.datetime.now() sockets=map(connect,ports) poems=dict.fromkeys(sockets,'')#socket->accumulatedpoem #socket->tasknumbers sock2task=dict([(s,i+1)fori,sinenumerate(sockets)]) sockets=list(sockets)#makeacopy whilesockets: #运用select来确保那些可读取的异步socket可以立即开始读取IO #OS不停的搜索目前可以read的socket,有的话就返回rlist rlist,_,_=select.select(sockets,[],[]) forsockinrlist: data='' whileTrue: try: new_data=sock.recv(1024) exceptsocket.error,e: ife.args[0]==errno.EWOULDBLOCK: break raise else: ifnotnew_data: break else: printnew_data data+=new_data task_num=sock2task[sock] ifnotdata: sockets.remove(sock) sock.close() print'Task%dfinished'%task_num else: addr_fmt=format_address(sock.getpeername()) msg='Task%d:got%dbytesofpoetryfrom%s' printmsg%(task_num,len(data),addr_fmt) poems[sock]+=data elapsed=datetime.datetime.now()-start print'Gotpoemsin%s'%elapsed
结果只需要4秒就完成了读取任务。效率是刚才同步socket的三倍。对客户端的异步改造主要有两点:
同步模式下,客户端分别创建socket;而在异步模式下,client开始就创建了所有的socket。
通过“sock.setblocking(0)”设置socket为异步模式。
通过Unix系统的select俩返回可读取IO
最为核心的是26行和29行。尤其是29行的select操作返回待读取socket的列表。