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MicroPython usockets not timing out

For various reasons, I am trying to have my ESP32 device with MicroPython poll all 256 options of 192.168.1.*:79 to find a 'host' PC. In doing so, the ESP32 attempts to create a socket and connect it to each possible address, i.e.:
while not connected:
try:
addr = generate_next_address()
s = usocket.socket()
s.connect(addr)
except OSError:
s.close()
continue
print("Found a connection!")
connected = True
When attempting to send a connection to a device that refuses the connect(), it is very quick to throw the exception and move onward. However, the problem is when it starts encountering devices that either don't respond or don't exist, it waits for a significant time before timing out.
Now, I've tried every variation of using usocket.settimeout(), usocket.setblocking(), uselect.poll(), and time.delay(), but I was unable to get anything to change the timeout period.
By setting blocking to false, the script immediately attempts all 256 addresses and then breaks out of the while loop, disallowing an opportunity to connect properly. Having blocking on completely ignores any timeout setting I attempt, continuing to take 15-20 seconds to timeout, as opposed to 1.
Is there something I'm not understanding about how this works? Is there a solution that is obvious but I have missed?

IDE Crash causes hung job on Server

Good Day All! I am using pyodbc to connnect to a Microsoft SQL server using a Native Client 11.0 ODBC connection. Occasionally something will happen to cause Spyder to crash resulting in my query to hanging on the server. When this happens, all variables are lost, so I'm not able to cancel the job that is still on the server or close the connection. My DBAs do not have rules in place to cancel long running queries, but hung queries like this block ETLs. I have my ODBC connection set up the way they've requested, so the question is, what else can I do to prevent issues for my partners when Spyder crashes? Note: I've imported pandas as "pd".
try:
data_conn = pyodbc.connect(dECTV)
data_conn.timeout = 1000
tfn = pd.read_sql(tele,data_conn)
print("Call information retrieved")
except:
print('!~!~!~!n Exception has been Raised for Inbound information!~!~!~!')
tfn = pd.read_csv(export_location + r'\TFN_Details.csv')
finally:
data_conn.close
print("Connection Closed. Moving on.")

BTW, I've done a lot of reading over the last two hours and have what I consider to be a solution, but I wanted to see if others agree. My thoughts would be to execute the following before running anything new on the same server.
exec sp_who 'my_login_id'; kill 'resulting_SPID';

Timeout for idle connection

I am using asyncore and asynchat modules to build a SMTP server (I used code from smtpd lib to build the SMTP server) but I have a problem with connection timeouts. When I open telnet connection to the SMTP server and leave it so, the connection is established althought no data exchange happens. I want to set timeout e.g 30 seconds and to close the idle connection by server if nothing comes from the client (else there could be an easy DOS vulnerability). I googled for a solution, read source codes and documentation but didn't found anything usable.
Thanks

According to asyncore documentation, asyncore.loop() has a timeout parameter, which defaults to 30 seconds. So apparently default already should be 30 seconds, you can try and play with it to suit your own needs.
The timeout argument sets the timeout parameter for the appropriate
select() or poll() call, measured in seconds; the default is 30
seconds.
Ok, the above actually refers to poll() or select() timeout and not the idle timeout.
As per this page, you can hack asyncore to support timeouts like this:
Add the following block to your own copy of asyncore.poll just after the for fd in e: block...
#handle timeouts
rw = set(r) + set(w)
now = time.time()
for f in (i for i in rw if i in map):
map[f].lastdata = now
for j in (map[i] for i in map if i not in rw):
if j.timeout+j.lastdata now:
#timeout!
j.handle_close()
You ARE going to need to initialize .timeout and .lastdata members for
every instance, but that shouldn't be so bad (for a socket that
doesn't time out, I would actually suggest a 1 hour or 1 day timeout).

Python 3.2.3: Socket takes longer to timeout than it should?

I'm using Python 3.2.3 on Windows 7, and one piece of code I have connects to a server with a blocking socket, with a user-specified timeout value. The code is simply:
testconn = socket.create_connection((host, port), timeout)
The code works fine, apart from the odd fact that timing out seems to take longer than it should on invalid requests. I tried connecting to www.google.com:59855 deliberately (random port should mean it should try connecting until it reaches the timeout), with a timeout of 5 seconds, but it seemed to take 15 seconds at least to timeout.
Are there any possible reasons for this, and/or any fixes? (It's not a huge problem if it's not fixable, but a solution would be appreciated nevertheless.) Thanks in advance.

This isn't an issue specific to Python 3 or Windows. Take a look at the docs for create_connection(): http://docs.python.org/library/socket.html#socket.create_connection
The important snippet is:
if host is a non-numeric hostname, it will try to resolve it for both
AF_INET and AF_INET6, and then try to connect to all possible
addresses in turn until a connection succeeds.
It resolves the name using socket.getaddrinfo. If you run
socket.getaddrinfo('google.com', 59855, 0, socket.SOCK_STREAM)
You'll probably get a few results returned. When you call socket.create_connection, it will iterate over all of those results, each waiting for timeout seconds until it fails. Because it waits timeout seconds for EACH result, the total time is obviously going to be greater than timeout.
If you call create_connection with an IP address rather than host name, e.g.
testconn = socket.create_connection(('74.125.226.201', 59855), timeout=5)
you should get your 5 second timeout.
And if you're really curious, take a look at the source for create_connection. It's pretty simple and you can see the loop that is causing your problems:
https://github.com/python/cpython/blob/3.2/Lib/socket.py#L408

How to timeout early when trying to connect

I have an application that is trying to connect to a rabbitmq-server, but I want my application to timeout within a specified number of seconds if it cannot connect to the server.
My problem is that I can't figure out how to do it.
to clarify, it's when my producer tries to connect that I want to timeout earlier, because now It takes up to 20-30 seconds.

If the library you're using makes use of the socket module (many do), a simple import socket; socket.setdefaulttimeout( SECONDS ) will suffice
[edited to include the correction by Daniel Figueroa]