[dnsdist] Clarification on weight in newServer option

Remi Gacogne remi.gacogne at powerdns.com
Mon Jul 31 08:32:44 UTC 2017

On 07/28/2017 11:13 AM, Frank Even wrote:
> I may very well have missed something, but a lot of this isn't clear
> to me in the documentation.  I appreciate the clarification though.

No, you are right, it's not clear in our documentation, I need to take
the time to fix it.

> SO, if I understand correctly, if I want the weight variable to have
> any meaning at all, I need to change the load balancing algorithm,
> correct?

Correct, the weight is only used by the wrandom and whashed policies at
the moment.

> What policy would be best suited to using weights?  Is that efficient?
>  Or should I just keep it like this, remove weights, and deploy an
> ordered policy?

My best advice would be to have a look at the existing policies based on
you exact needs. If you can't find a policy matching your needs, you can
write a new one in Lua or, if you think it would make sense to add a new
one in dnsdist, open a feature request.
Policies written in Lua are not a lot slower than those written in C++
given that they are written carefully. They do increase lock contention
between threads a bit however, but that's only relevant if you serve a
huge number of QPS.

Remi Gacogne
PowerDNS.COM BV - https://www.powerdns.com/

-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 488 bytes
Desc: OpenPGP digital signature
URL: <http://mailman.powerdns.com/pipermail/dnsdist/attachments/20170731/521c422c/attachment.sig>

More information about the dnsdist mailing list