On Wed, Oct 10, 2012 at 10:12:51PM +0200, Strahinja Kustudić wrote: > @Bruce Thanks for your articles, after reading them all I don't think > disabling > swap is a good idea now. Also you said to see the effective_cache_size I > should > check it with free. My question is should I use the value that free is showing > as cached, or a little lower one, since not everything in the cache is because > of Postgres.
Well, you are right that some of that might not be Postgres, so yeah, you can lower it somewhat. > @Claudio So you are basically saying that if I have set effective_cache_size > to > 10GB and I have 10 concurrent processes which are using 10 different indices > which are for example 2GB, it would be better to set the effective_cache size > to 1GB? Since if I leave it at 10GB each running process query planner will > think the whole index is in cache and that won't be true? Did I get that > right? Well, the real question is whether, while traversing the index, if some of the pages are going to be removed from the cache by other process cache usage. effective_cache_size is not figuring the cache will remain between queries. -- Bruce Momjian <br...@momjian.us> http://momjian.us EnterpriseDB http://enterprisedb.com + It's impossible for everything to be true. + -- Sent via pgsql-performance mailing list (pgsql-performance@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
