Am 12.09.2011 15:37, schrieb Peter van Dijk: > Hello Klaus, > > On Sep 12, 2011, at 12:40 PM, Klaus Darilion wrote: > >> Am 09.09.2011 19:40, schrieb bert hubert: >>> >>> Can you try 'query-cache-ttl=200' and see if this improves >>> things? If it does, it would help us solve the issue. >> >> Which DB-queries will be cached by PDNS? Only DNS-query related >> DB-queries, or all DB-queries (e.g. slave-cycle-interval triggered >> queries)? > > All queries to the 'records' table (for SOA and for other resource > types) are eligible for the query cache.
Obviously not all. For example if I trigger NOTIFYs from the master, I see multiple SOA lookups in the DB, although DNS-SOA queries to the slave will be answered without DB-queries directly from cache. >> And what happens if the SLAVE updates the DB due to an incoming >> AXFR. Will it also expire relevant cache entries? > > As far as I know, the TTL (which Bert suggests to set to 200) is the > only thing managing expiry. So, no, there would be no automatic > expiry on a slave domain update. However, we're not suggesting > query-cache-ttl as a fix; we are wondering whether changing it like > that would make a difference in your observed performance, just as a > debugging aid. No, that does not help. I have set query-cache-ttl=100 and slave-cycle-interval=60. When the "slave-admin" queries would be cached as well, then I should see queries only every 2 minutes. But I still see the 10 000 SOA DB-queries every minute. Thus, it seems that "management" DB-queries are not affected by the query-cache. regards Klaus _______________________________________________ Pdns-users mailing list [email protected] http://mailman.powerdns.com/mailman/listinfo/pdns-users
