I am using Django to serve an application, and I noticed some slowing down recently.
So I went and checked the console that serves the server, that usually logs lines of this format :
<date_time> "GET <path> HTTP/1.1" <HTTP_STATUS> <response_time>
What I thought was the response time in milliseconds is apparently not, as I get values that would be ludicrous (example 3923437 for a query that when timed in python directly takes 0.936 seconds). I'm pretty sure it's a response time though, as it's always scaled with the time I wait.
Can someone explain to me what that number is ? I couldn't find where this default log is documented.
That number is not the response time, your question title is incorrect.
It's the response size and it's printed by Python http-server which Django inherits. That explains why it's not documented by Django, because it's not the Django code that prints it.
You can verify that by looking at this Django module. This is the line that starts the http-server.
It inherits from Python http-server. This is the line that prints the response size.