Mladen Gogala wrote:
Where can I find the documentation describing the buffer replacement policy? Are there any parameters governing the page replacement policy?
I wrote a pretty detailed description of this in my "Inside the PostgreSQL Buffer Cache" presentation at http://projects.2ndquadrant.com/talks and nothing in this specific area has changed significantly since then. There aren't any specific tunables in this area beyond the ones that cover sizing of the buffer pool and how often checkpoints happen. There's a TODO item to benchmark toward whether there's any gain to increasing the maximum usage count an individual page can accumulate, currently hard coded at 5. That's the main thing that could be tunable in this area that currently isn't.
-- Greg Smith 2ndQuadrant US greg@xxxxxxxxxxxxxxx Baltimore, MD PostgreSQL Training, Services and Support www.2ndQuadrant.us "PostgreSQL 9.0 High Performance": http://www.2ndQuadrant.com/books -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
