Aaron Turner wrote:
Are newer PG versions more memory efficient?
Moving from PostgreSQL 8.1 to 8.3 or later should make everything you do happen 2X to 3X faster, before even taking into account that you can tune the later versions better too. See http://suckit.blog.hu/2009/09/29/postgresql_history for a simple comparison of how much performance jumped on both reads and writes in the later versions than what you're running. Memory consumption will on average decrease too, simply via the fact that queries start and finish more quickly. Given an even workload, there will be less of them running at a time on a newer version to keep up.
Given the size of your database, I'd advise you consider a migration to a new version ASAP. 8.4 is a nice stable release at this point, that's the one to consider moving to. The biggest single problem people upgrading from 8.1 to 8.3 or later see is related to changes in how data is cast between text and integer types; 1 doesn't equal '1' anymore is the quick explanation of that. See http://wiki.postgresql.org/wiki/Version_History for links to some notes on that, as well as other good resources related to upgrading. This may require small application changes to deal with.
Even not considering the performance increases, PostgreSQL 8.1 is due to be dropped from active support potentially as early as next month: http://wiki.postgresql.org/wiki/PostgreSQL_Release_Support_Policy
Also: PostgreSQL 8.1.3 has several known bugs that can lead to various sorts of nasty data corruption. You should at least consider an immediate upgrade to the latest release of that version, 8.1.22. Small version number increases in PostgreSQL only consist of serious bug fixes, not feature changes. See http://www.postgresql.org/support/versioning for notes about the project's standard for changes here, and how it feels about the risks of running versions with known bugs in them vs. upgrading.
-- Greg Smith, 2ndQuadrant US greg@xxxxxxxxxxxxxxx Baltimore, MD PostgreSQL Training, Services and Support www.2ndQuadrant.us Author, "PostgreSQL 9.0 High Performance" Pre-ordering at: https://www.packtpub.com/postgresql-9-0-high-performance/book -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
