我在python中编写了一个epoll包装器,它工作正常,但是最近我发现性能对于大包发送来说并不理想。我期待下入代码,发现居然有错误在Python epoll中,我可以避免errno.EWOULDBLOCK,errno.EAGAIN?
Traceback (most recent call last):
File "/Users/dawn/Documents/workspace/work/dev/server/sandbox/single_point/tcp_epoll.py", line 231, in send_now
num_bytes = self.sock.send(self.response)
error: [Errno 35] Resource temporarily unavailable
和以前沉默它作为文件说,所以我的发送功能做这样的LOT:
def send_now(self):
'''send message at once'''
st = time.time()
times = 0
while self.response != '':
try:
num_bytes = self.sock.send(self.response)
l.info('msg wrote %s %d : %r size %r',self.ip,self.port,self.response[:num_bytes],num_bytes)
self.response = self.response[num_bytes:]
except socket.error,e:
if e[0] in (errno.EWOULDBLOCK,errno.EAGAIN):
#here I printed it, but I silent it in normal days
#print 'would block, again %r',tb.format_exc()
break
else:
l.warning('%r %r socket error %r',self.ip,self.port,tb.format_exc())
#must break or cause dead loop
break
except:
#other exceptions
l.warning('%r %r msg write error %r',self.ip,self.port,tb.format_exc())
break
times += 1
et = time.time()
我GOOGLE了它,并说它是由临时网络缓冲区耗尽导致的 那么如何手动和有效地检测到这个错误,而不是进入异常阶段?
因为它导致rasie /处理异常很多时间。
确定我知道这会发生将套接字缓冲区已满,所以我手动增加它sock.setsockopt(socket.SOL_SOCKET,socket.SO_SNDBUF,1024 * 1024 * 10) ,并会降低例外率 – davyzhang