2011/9/19 Vitalii Tymchyshyn <tivv00@xxxxxxxxx>: > 17.09.11 23:01, Stefan Keller написав(ла): >> >> * more... ? > > What I miss from my DB2 UDB days are buffer pools. In PostgreSQL terms this > would be part of shared buffers dedicated to a relation or a set of > relations. When you have a big DB (not fitting in memory) you also usually > want some small tables/indexes be in memory, no matter what other load DB > has. > Complimentary features are: > 1) Relations preloading at startup - ensure this relation are in memory. you can use pgfincore extension to achieve that, for the OS cache. It does not look interesting to do that for shared_buffers of postgresql (the subject has been discussed and can be discussed again, please check mailling list archieve first) > 2) Per buffer pool (or relation) page costs - tell it that this > indexes/tables ARE in memory you can use tablespace parameters (*_cost) for that, it has been rejected for tables in the past. I did propose something to start to work in this direction. See "[WIP] cache estimates, cache access cost" in postgresql-hackers mailling list. This proposal let inform the planner of the table memory usage and take that into account. > > Best regards, Vitalii Tymchyshyn. > > -- > Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) > To make changes to your subscription: > http://www.postgresql.org/mailpref/pgsql-performance > -- Cédric Villemain +33 (0)6 20 30 22 52 http://2ndQuadrant.fr/ PostgreSQL: Support 24x7 - Développement, Expertise et Formation -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
