Message-ID: <4318934E.7070404@travelamericas.com>
Date: Fri, 02 Sep 2005 11:00:46 -0700
From: Chris Travers <chris@travelamericas.com>
User-Agent: Mozilla Thunderbird 1.0 (X11/20041206)
MIME-Version: 1.0
To: Akshay Mathur <akshay.mathur@airtightnetworks.net>
Cc: 'Ron' <rjpeace@earthlink.net>, pgsql-performance@postgresql.org
Subject: Re: Massive performance issues
References: <002901c5afa0$0dcddab0$8301a8c0@pune.wibhu.com>
In-Reply-To: <002901c5afa0$0dcddab0$8301a8c0@pune.wibhu.com>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
Content-Transfer-Encoding: 7bit

Akshay Mathur wrote:

>Ron,
>
>Can you give me some pointers to make the tables RAM resident. If one
>does so, is the program accessing the data need to change. Does pgsql
>take care to write the data to disk?
>
>  
>
PostgreSQL tried to intelligently cache information and then will also 
use the OS disk cache as a secondary cache.  So a sufficiently small and 
frequently accessed table will be resident in RAM.

The simplest way to affect this calculus is to put more RAM in the 
machine.  There are hacks I can think of to create RAM caches of 
specific tables, but I don't want to take responsibility for anyone 
trying these and running into trouble.

Best Wishes,
Chris Travers
Metatron Technology Consulting