Re: Issues with 400+ back end web servers?

From: Willy Tarreau <>
Date: Thu, 13 Aug 2009 22:32:14 +0200

On Thu, Aug 13, 2009 at 01:30:00AM +0200, wrote:
> Jayme Cox a écrit :
> >Hi,
> >
> >We are running haproxy with almost 400 back end web servers and I was
> >wondering if we are going to run into any limitations or performance
> >issues with that many?
> >
> >There are only ~5 connections to each server, with most of them very
> >small and short lived, transfering an average of 5 kb per connection.
> >
> Wouaw, 400 web server for ~10Mbps of generated traffic ?
> that look like quite an inefficient use of a web server...
> I'm sorry but i have to ask: what could justify the deploiment of
> such an overwhelming configuration for so little output ?

I agree this sounds very strange and seems almost unmanageable...

Anyway, you should not expect any particular problem. The only thing I can see is that if you use cookie-based persistence, each new connection willl scan the list of servers to find the first one supporting the cookie. But that's not more expensive than ACLs or similar processing. I still expect a few thousands hits/s with 400 servers on a common machine.

Willy Received on 2009/08/13 22:32

This archive was generated by hypermail 2.2.0 : 2009/08/13 22:45 CEST