Nginx response rate increases with more upstream ports

[Igor Sysoev]

On Tue, Jun 16, 2009 at 11:50:16AM +0530, Asif Ali wrote:

> Dear All,
> I am trying to resolve a particular issue that is not getting solved easily.
> 
> Nginx is able to route requests but the speed of routing is slowing
> down..when I am increasing the number of upstream ports.
> 
> I have an app which responds in under 500ms. When I route those requests
> through nginx to about 50 ports, nginx response rates increases to 1500-2500
> ms whereas the app can handle large concurrent requests and there are as
> many as 50 ports.
> 
> I have tried this with both fair and e-y load balancer but with similar
> results.
> 
> I have also tuned nginx configuration for response times, timeouts etc but
> still I see similar results.
> 
> Can anyone advise me if they have experienced a similar problem earlier and
> if they have a solution for this?.

What do you mean by upstream ports ? This

    upstream backend {
        server  backend:9000;
        server  backend:9001;
        server  backend:9002;
        server  backend:9003;
        ...
    }

?

In this case you run 50 backend processes and they compete for CPU.


-- 
Igor Sysoev
http://sysoev.ru/en/