Hi Anders, Generally larger cache memory can improve latency (cache hit ratio) because it can keep more records in cache. I'm not certain whether too much memory introduce something harmful or not (except power consumption or failure rate of memory modules).
But according to my test, around 3-4GBs memory per one Unbound cache server seems to be enough (e.g. rrset-cache-size: 2g, msg-cache-size: 1g) even if in large ISP environment. More memory won't improve cache hit ratio meaningfully. PowerDNS recursor doc gives similar suggestion [1]. Note that Unbound will consume more memory than you specified due to malloc() overhead [2] and we will need more cache memory as DNSSEC-signed zone is deployed more widely. [1] http://doc.powerdns.com/html/recursor-performance.html "Cache hit rate does not improve meaningfully beyond 4 million max-cache-entries per thread…. " [2] http://www.unbound.net/documentation/howto_optimise.html -- Daisuke HIGASHI <[email protected]> _______________________________________________ Unbound-users mailing list [email protected] http://unbound.nlnetlabs.nl/mailman/listinfo/unbound-users
