Python 子进程调用效率

Question

我正在编写一个 python 程序，它可以 ping 设备并报告 online/offline 状态和延迟。现在它工作正常，但只要有设备离线或不响应，输出就会挂起大约 5 秒。

我的问题是我可以独立地而不是顺序地 ping 所有东西 and/or 我可以在子进程上设置某种时间过滤器吗，如果在 ~100-200 毫秒后没有更新，它会移动继续下一个？

这是我目前正在处理的代码的相关部分

for item in lines:
#remove whitespaces, etc from item.
hostname = item.rstrip()

#Run ping and return output to stdout.
#subprocess.Popen runs cmdline ping, pipes the output to stdout. .stdout.read() then reads that stream data and assigns it to the ping_response variable
ping_response = subprocess.Popen(["ping", hostname, "-n", '1'], stdout=subprocess.PIPE).stdout.read()
word = "Received = 1"
word2 = "Destination host unreachable."

#Regex for finding the time values and inputting them in to a list.
p = re.compile(ur'(?<=time[<=])\S+')
x = re.findall(p, ping_response)
if word2 in ping_response:
    print "Destination Unreachable"
elif word in ping_response:
    print "%s is online with latency of " % hostname +x[0]
else:
    print "%s is offlineOffline" % hostname

Answer 1

My question is can I either ping everything independently and not sequentially

当然可以。该问题有多种解决方案，包括 threading 和 multiprocessing 模块。

and/or can I set a time filter of some sort on the subprocess so that, if things aren't updated after ~100-200ms it moves on to the next?

您实际上可以在 ping 本身上设置超时，至少是 Linux 版本，使用 -W 选项：

   -W timeout
          Time to wait for a response, in seconds. The option affects only
          timeout in absence of any responses, otherwise  ping  waits  for
          two RTTs.

Answer 2

Ping 具有超时功能，这将有助于提高脚本的效率。

-W waittime
             Time in milliseconds to wait for a reply for each packet sent.  If a reply arrives later, the packet
             is not printed as replied, but considered as replied when calculating statistics.

此外，here 是其他一些可以有效 ping 的实用程序。

Python 子进程调用效率

Python subprocess call efficiency

python

subprocess