haproxy maxconn meaning

Question

In the haproxy config file, there is a directive called maxconn.

does this directive refer to concurrent connections? Or once the connection is redirected to a server, it is closed? For example, if the maxconn is set to 4000, and in my whole website there are 10k people, would that directive limit that users number?

Thank you

score 1 · Answer 1 · answered Apr 22 '12 at 22:00

1

It sets the maximum number of concurrent connections. Each connection lasts as long as that request (or, with keep-alive, that set of requests).

So, yes, if all 10,000 users are making a request at the exact same time, then a maxconn setting of 4000 will limit that.

Additionally, most modern browsers open more than one TCP connection when they have a long list of resources to request - this multiplexing allows for resources to load more quickly in general, but increases the effective number of connections that your load balancer sees.

answered Apr 22 '12 at 22:00

Shane Madden

114,520
13
181
251

then, how can I make haproxy hold more than number of users? – Enrico Tuttobene Apr 22 '12 at 22:05
@EnricoTuttobene: Simply, increase the limit to an acceptable value. – Khaled Apr 23 '12 at 07:21
yea but what about when i will have 100 machines and 100.000 connections? maybe more? still they all rely on the loadbalancer server. – Enrico Tuttobene Apr 23 '12 at 15:24
You'll need scale to more than one load balancer eventually. – Shane Madden Apr 23 '12 at 16:44

haproxy maxconn meaning

1 Answers1