Hello guys, Have a question concerning a round robin balancing scenario where a session cookie is used. Additionally to the session cookie (and therefore re-use of the same backend server) there is a maxconn setting of 6 per backend server, allowing 6 concurrent connections.
Benchmarking tests have showed that concurrent connections 7+ are being queued. This should not happen, HAProxy should return a http error back to the client (much like backend down). I thought I could tackle this with "maxqueue 1" for each backend server. This setting works for 8+ concurrent connections; HAProxy returns a HTTP 503 error to the client. But the 7th connection is still being queued. Is there a way to disable queuing at all for a backend? Current config: backend app-out balance roundrobin no option redispatch cookie SERVERID insert indirect nocache option httpchk GET /service?wsdl HTTP/1.0\r\nConnection:\ close server app01-18383 10.10.10.11:18383 maxconn 6 maxqueue 1 cookie 1-18383 check fall 1 rise 2 server app01-18384 10.10.10.11:18384 maxconn 6 maxqueue 1 cookie 1-18384 check fall 1 rise 2 server app01-18385 10.10.10.11:18385 maxconn 6 maxqueue 1 cookie 1-18385 check fall 1 rise 2 server app01-18386 10.10.10.11:18386 maxconn 6 maxqueue 1 cookie 1-18386 check fall 1 rise 2 server app01-18387 10.10.10.11:18387 maxconn 6 maxqueue 1 cookie 1-18387 check fall 1 rise 2 server app01-18388 10.10.10.11:18388 maxconn 6 maxqueue 1 cookie 1-18388 check fall 1 rise 2 server app01-18389 10.10.10.11:18389 maxconn 6 maxqueue 1 cookie 1-18389 check fall 1 rise 2 server app01-18390 10.10.10.11:18390 maxconn 6 maxqueue 1 cookie 1-18390 check fall 1 rise 2 server app02-18383 10.10.10.12:18383 maxconn 6 maxqueue 1 cookie 2-18383 check fall 1 rise 2 server app02-18384 10.10.10.12:18384 maxconn 6 maxqueue 1 cookie 2-18384 check fall 1 rise 2 server app02-18385 10.10.10.12:18385 maxconn 6 maxqueue 1 cookie 2-18385 check fall 1 rise 2 server app02-18386 10.10.10.12:18386 maxconn 6 maxqueue 1 cookie 2-18386 check fall 1 rise 2 server app02-18387 10.10.10.12:18387 maxconn 6 maxqueue 1 cookie 2-18387 check fall 1 rise 2 server app02-18388 10.10.10.12:18388 maxconn 6 maxqueue 1 cookie 2-18388 check fall 1 rise 2 server app02-18389 10.10.10.12:18389 maxconn 6 maxqueue 1 cookie 2-18389 check fall 1 rise 2 server app02-18390 10.10.10.12:18390 maxconn 6 maxqueue 1 cookie 2-18390 check fall 1 rise 2 Thanks, ck PS: Yes, "no option redispatch" has been set on this backend. Purposely to not redispatch to another backend server if an existing session (cookie) is detected. For this specific application setup it's better to get a HTTP error than to break the session.
