Winsock是否限制并发连接数？

Question

I've recently made a program in C# (stress tester), which creates an array of 100,000 sockets, and connects each of them to a specified server.

Every time I have tested this, the program stopped at 16,334 sockets. The last connected socket was socket 16,334. They all stayed connected until I closed them, but still I couldn't connect more than 16,334 sockets to the same server.

Why does it happen? Is it a limitation of Winsock?

If so, can it somehow be bypassed?

Answer 1

There are limits on the number of outbound connections that you can make and knowing exactly what you mean by "stopped at" would likely help determine your problem. Which API is returning which error code causing you to "stop"?

The limits tend to be related to availability of ephemeral ports (see MaxUserPort ) and available memory and/or non-paged pool (though the later is rarely an issue on Vista or later).

You might trying running netstat when your process "stops" as this will show how many other processes also have connections established and are using ephemeral ports.

You could also take a look here , as depending on the OS that you're running on some of the information may be of use to you.