[Pdns-users] Wanted: Little Lua script creating

Peter van Dijk peter.van.dijk at netherlabs.nl
Mon Sep 15 07:59:56 UTC 2014


Hello Steven,

On 12 Sep 2014, at 17:36 , Steven Maddox <s.maddox at lantizia.me.uk> wrote:

> 2) Don't ask me not to use MySQL - it's what our internal developers
> know how to stick data in to... however I appreciate caching this data
> to something else might handy to read from that instead.

Just one very important thing here - the Recursor has only one Lua instance per thread (threads= setting in recursor.conf), and if this Lua instance is waiting for MySQL to respond, that thread is not handling any other queries. Increasing the thread count to deal with this is unfeasible for any non-trivial traffic amount.

Because of this, we recommend caching your data either to a local format that is quick and non-blocking (bdb, lmdb, *maybe* sqlite), or into actual Lua tables that you can index into quickly because you’ve loaded them all into memory. Don’t reject the second option because of memory constraints - your local on-disk database will have to be cached in RAM anyway to get good performance.

Kind regards,
-- 
Peter van Dijk
Netherlabs Computer Consulting BV - http://www.netherlabs.nl/

-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 841 bytes
Desc: Message signed with OpenPGP using GPGMail
URL: <http://mailman.powerdns.com/pipermail/pdns-users/attachments/20140915/201674ad/attachment-0001.sig>


More information about the Pdns-users mailing list