nginx performance using resolver

[Igor Sysoev]

On Thu, Feb 05, 2009 at 06:57:16PM +0100, Nginx Lova wrote:

> Igor Sysoev wrote:
> > On Thu, Feb 05, 2009 at 04:20:31PM +0100, Nginx Lova wrote:
> > 
> >> >     resolver_timeout  2s;
> >> > 
> >> 
> >> Does this expire the records the resolver knows about ?
> > 
> > No, this resolving timeout only.
> > The expiration time is currently hardcoded to 5 minutes.
> > 
> 
> So this sets the resolver to timeout at a specific type of search ?
> 
> first it checks upstreams then dns , so does this set the timeout for 
> upstreams to 2s ? then the dns to 2s ?

No, first nginx looks up a host in upstream's. There is no timeout.
If the host is not defined as upstream, then nginx tests it as IP address.
If the host is not IP address, then nginx tries to resolve the host.
The timeout is used here while resolving.


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