Re: [Exim] Caching DNS and Exim

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Auteur: Nigel Metheringham
Date:  
À: Dave Rigby
CC: exim-users
Sujet: Re: [Exim] Caching DNS and Exim
drigby@??? said:
> I'm thinking of setting up a caching-only DNS server on my mail
> server, to try and speed up Exim. Has anyone else tried it, and is the
> performance increase (if any) worth the effort ?


Unhelpfully... it depends!
If you have a nearby (ie direct ethernet connected DNS server with
sufficient resources) DNS server then its unlikely to make much
difference and could possibly be slower to use a same machine server
due to context switches.

DNS servers need memory. If a local server would be pushed into swap
then thats seriously bad.

In theory a local ncsd or similar cache could be good. In practice
they are evil and should be destroyed immediately :-)

    Nigel.
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[ Nigel Metheringham                  Nigel.Metheringham@??? ]
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