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Recently I ran into some issue related to the UDP sending on Windows. When the application tries to send the packets over UDP in non-blocking mode, often it received socket error 10035 (WSAEWOULDBLOCK) in the send(), so likely that the socket buffer is full. I only seen this issue on Windows 2008 and did not see the same problem on Windows 2003.

I was doing some research and found the following article (although it mention TCP)

At the bottom it mentioned updating of the registry value HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\AFD\Parameters\NonBlockingSendSpecialBuffering to 1

But it didn't include further details

Would anyone know what is the effect of setting this registry value and what does it do?

I tried to research on the web but unable to find any reference, including the msdn website.

Any help would be appreciated.

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this is the MSDN reference :

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While this link may answer the question, it is better to include the essential parts of the answer here and provide the link for reference. Link-only answers can become invalid if the linked page changes. – Michael Hampton Sep 3 '12 at 7:49

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