Message-ID: <47979C15.3040406@burntmail.com>
Date: Wed, 23 Jan 2008 14:57:09 -0500
From: Guy Rouillier <guyr-ml1@burntmail.com>
User-Agent: Thunderbird 2.0.0.9 (Windows/20071031)
MIME-Version: 1.0
To: pgsql-performance@postgresql.org
Subject: Re: Making the most of memory?
References: <4796BE84.9030803@centriccrm.com>	
	<dcc563d10801222120q78e390dbj2b884eca729c2975@mail.gmail.com>	
	<B30794E6-CD2A-43C1-B431-E24B56FBFB1D@concursive.com>
	<dcc563d10801231044p1dba892r9b8bf1269395f068@mail.gmail.com>
In-Reply-To: <dcc563d10801231044p1dba892r9b8bf1269395f068@mail.gmail.com>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
Content-Transfer-Encoding: 7bit

Scott Marlowe wrote:
> I assume you're talking about solid state drives?  They have their
> uses, but for most use cases, having plenty of RAM in your server will
> be a better way to spend your money.  For certain high throughput,
> relatively small databases (i.e. transactional work) the SSD can be
> quite useful.

Unless somebody has changes some physics recently, I'm not understanding 
the recent discussions of SSD in the general press.  Flash has a limited 
number of writes before it becomes unreliable.  On good quality consumer 
grade, that's about 300,000 writes, while on industrial grade it's about 
10 times that.  That's fine for mp3 players and cameras; even 
professional photographers probably won't rewrite the same spot on a 
flash card that many times in a lifetime.  But for database 
applications, 300,000 writes is trivial. 3 million will go a lot longer, 
but in non-archival applications, I imagine even that mark won't take 
but a year or two to surpass.

-- 
Guy Rouillier