Re: windows 10 / udp packet loss, off-topic ?

[Frédéric LOCHON <f.lochon () hirex fr>]

Le 18/07/2016 à 15:50, Frédéric LOCHON a écrit :
> Hello,
>
> I'm facing a strange behavior on Windows 10 computers.
> That's a little bit off-topic, but I give it a try.
>
> Since I upgraded to Windows 10, I get some packet loss from Windows:
> - I get an UDP packet every 10 ms or so coming from some equipment I 
> have on my network.
> - I do see every packet in Wireshark (which means the link is OK).
> - I don't see every packet in "Windows" (using winsock API), I loose 
> about 1 to 5 packets every second (not very regularly).

Hello,

I think I found the problem.

In fact, I found a solution some time ago and was lacking of time to 
share it.


In my application, I get a UDP packet roughly every 16 ms (very 
regularly) and I was doing something like this:

    setsockopt(socketHandle, SOL_SOCKET, SO_RCVTIMEO, (char*)&timeout, 
sizeof(int));
    if(recvfrom(socketHandle, data, maxSize, 0, (LPSOCKADDR)&sin, 
&fromSize) < 0)
...

With a timeout value of 10 ms, I loose some packets (Wireshark sees 
them, not my application).
With a timeout value of 100 ms, I don't loose any packets.

I don't quite understand the relationship. But it has proven to be the 
solution.
To me, that sounds like a bug in Windows, unless anybody has some other 
explanation.

Anyway, maybe that will be useful to someone one day...

Best regards,

Frédéric Lochon.

___________________________________________________________________________
Sent via:    Wireshark-users mailing list <wireshark-users () wireshark org>
Archives:    https://www.wireshark.org/lists/wireshark-users
Unsubscribe: https://www.wireshark.org/mailman/options/wireshark-users
            mailto:wireshark-users-request () wireshark org?subject=unsubscribe