Simple Non blocking TCP Server and client to simulate the socket error 104 and 107 at the client side.

For more details about this repo, please read my blog entry -

http://haridas.in/what-happens-when-we-hit-the-speed-limit-of-python.html

Start the C server. Which listening on the port 8000 and handles the Client connections on another thread.

$ gcc tcp_server.c
$ ./a.out

On another shell environemnt run python client. It has two options -

1. Run the Python client which gives the error 104 and 107 issue. Which is the issue I'm getting right now on the production machine.

2. Another implementation of the Python client which fixes the issue and read the socket data without causing socket error 104 and 107

Bellow command will crash after a while since the server closes the socket on its side due to the kernel sending buffer is full on the server side.

$ python tcp_server.py  # Simulate the tcp client with socket problem.

Bellow command will read the socket data in non-blocking mode and read entire data from the socket till it throws EAGAIN exception.

$ python tcp_server.py -c # This client has the option to fix that issue.

This time the client won't throw any excetion and the server and client work smoothly. So finally I got the protype to fix the actual production system.

To See what is happening while running this scripts run tcpdump caommand.

$ sudo tcpdump -i any port 8000