i HAProxy community, As a new user of HAproxy, I'm puzzled by the definition of "sessions" in HAproxy. I can't seem to find it anywhere in docs.
Test setup:- - HAproxy instance with one frontend, one backend and a stats frontend. - Backend connects to a custom Go program that supports persistent connections. - Load-testing program "hey" doing "1 req per sec" over "1 tcp connection". Full configs are available here: https://gist.github.com/shadyabhi/fc511449600092364b08e58e2b07079f After 10s of starting the experiment, this is what I see on stats page:- - On "http frontend", the stats page shows "0 session rate", which makes sense because "hey" is reusing TCP connections for multiple HTTP requests. - On "default_backend backend", it appears that the session is incremented on each HTTP transaction. Wait, does a session on frontend doesn't mean the same session at backend? - Session reuse seems to be 90%, so it's unlikely that the backend is creating a new TCP connection (aka session??) to serve every request initiated by "hey". I see sessions being used here (https://www.haproxy.com/documentation/hapee/latest/configuration/variables/syntax/#scoping), and it seems to suggest that session signifies a "tcp session". That holds true for frontend, but not for backend as per the above experiment. So, what really is a session? Stats page link: https://gist.github.com/shadyabhi/fc511449600092364b08e58e2b07079f -- Cheers, Abhijeet (https://abhi.host)
