11 messages in ru.sysoev.nginxRe: HTTP load balancing algorithm| From | Sent On | Attachments |
|---|---|---|
| Florian Munz | Jan 22, 2007 11:41 am | |
| Igor Sysoev | Jan 22, 2007 12:28 pm | |
| Jonathan Vanasco | Jan 22, 2007 12:43 pm | |
| Ezra Zygmuntowicz | Jan 22, 2007 1:01 pm | |
| Florian Munz | Jan 22, 2007 1:10 pm | |
| Igor Sysoev | Jan 22, 2007 1:11 pm | |
| Igor Sysoev | Jan 22, 2007 1:15 pm | |
| Ezra Zygmuntowicz | Jan 22, 2007 1:19 pm | |
| Bob Ippolito | Jan 22, 2007 1:21 pm | |
| Aleksandar Lazic | Jan 22, 2007 11:22 pm | |
| Jure Pečar | Jan 23, 2007 12:27 am |
| Subject: | Re: HTTP load balancing algorithm | |
|---|---|---|
| From: | Bob Ippolito (bob-...@public.gmane.org) | |
| Date: | Jan 22, 2007 1:21:36 pm | |
| List: | ru.sysoev.nginx | |
On 1/22/07, Ezra Zygmuntowicz <ezmo...@public.gmane.org>
wrote:
On Jan 22, 2007, at 12:43 PM, Jonathan Vanasco wrote:
On Jan 22, 2007, at 3:28 PM, Igor Sysoev wrote:
I do not know ROR and Mongrel, but as I understand you may try to route slow requests to the dedicated backends:
that's what I thought of too, and you can do that with any proxy ( though i prefer nginx )
i'd be deathly scared of running a loadbalancer that automagically handled slow/fast requests the way you expect. the configuration would be a nightmare, and it would be doing so much logging and profiling of request timings, it might negate the purpose of a load balancer to begin with.
// Jonathan Vanasco
The ideal way that nginx's proxy could work best for rails/mongrel backends would be an optional proxy setting for not sending a request to a backend until said backend returns from a request.
That's the same as having a connection limit of 1.
Optimal load balancing is a hard problem and is highly dependent on the application and what it does. Another solution would be to send out a barrage of "pings" (e.g. a HEAD request) to servers that have a connection already and see which ones respond and weight them according to that. Such a solution might also detect dead servers (and also find servers when they come back from the dead).
-bob