The timeout settings are not working

[Bor-is-luv]

Hello! I am using Python 3.11.6, redis-py version 4.6.0 and hiredis 2.0.0. My application I run in Docker Python:3.11.6-slim-bookworm. I set up the timeout settings as follows: socket_connect_timeout=0.008 and socket_timeout=0.01. In addition to this, I set the following parameters: socket_keepalive=True, decode_responses=False. After which I began to measure the operation time of MGET. According to the measurement results, I clearly see that the response time sometimes exceeds 0.1 seconds. See screenshot below.

My question is why the timeout settings did not work and the MGET operation took 0.1 seconds instead of 0.01 seconds. To solve this problem, I tried: 1) Disabling hiredis. This didn't help. The response time also sometimes exceeds 0.01 seconds. 2) Passing the setting 'socket_keepalive_options': {socket.TCP_USER_TIMEOUT, 3}. This also didn't help. 3) Studying the original client code. I discovered that in the Connection class there is a method called can_read, which has an argument for timeout, which by default is set to 0, meaning that the timeout is absent and the completion of the operation will be awaited infinitely. I used monkey patching and redefined this method to my own, in which case when the timeout is equal to 0, the socket_timeout setting was used. But this also didn't help.

What else can I do? Can this be a bug in the original client code?

[harshit98]

@Bor-is-luv

Can you share the code reference for 3rd point ? Ideally, I was also looking into the client code and came across this piece of code, but from where timeout is not being passed into this function - I'm unable to figure that out.

def can_read(self, timeout=0):
        """Poll the socket to see if there's data that can be read."""
        sock = self._sock
        if not sock:
            self.connect()

        host_error = self._host_error()

        try:
            return self._parser.can_read(timeout)
        except OSError as e:
            self.disconnect()
            raise ConnectionError(f"Error while reading from {host_error}: {e.args}")

[Bor-is-luv]

@harshit98 in the third point I tried this solution

from redis.connection import Connection

original_function = Connection.can_read

def function(self: Connection, timeout: float = 0) -> bool:
    if not isinstance(timeout, (int, float)) or timeout <= 0:
        if self.socket_timeout is not None:
            timeout = self.socket_timeout
    return original_function(self, timeout)

Connection.can_read = function