To: pgsql-performance@postgresql.org
From: Thomas Kellerer <spam_eater@gmx.net>
Subject: Re: PG as in-memory db? How to warm up and re-populate buffers? How
	to read in all tuples into memory?
Date: Sun, 26 Feb 2012 12:46:03 +0100
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Stefan Keller wrote on 26.02.2012 01:16:
> 2. Are there any hints on how to tell Postgres to read in all table
> contents into memory?

What about creating tablespace on a RAM Fileystem (tmpfs), then create a second schema in your database where all tables are located in the that "temp" tablespace.

Then upon startup (or using triggers) you can copy all data from the persistent tables to the memory tables.

It would probably make sense to change the value of random_page_cost for that tablespace to 1

I'm not sure though how PostgreSQL handles a system-restart with tables on a tablespace that might not be there.

Thomas