Message-ID: <4D916649.6030601@krogh.cc>
Date: Tue, 29 Mar 2011 06:55:37 +0200
From: Jesper Krogh <jesper@krogh.cc>
User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US;
	rv:1.9.2.13) Gecko/20101208 Thunderbird/3.1.7
MIME-Version: 1.0
To: Merlin Moncure <mmoncure@gmail.com>
CC: Andy <angelflow@yahoo.com>,
	"pgsql-performance@postgresql.org" <pgsql-performance@postgresql.org>,
	Greg Smith <greg@2ndquadrant.com>
Subject: Re: Intel SSDs that may not suck
References: <4D90EDB6.2080609@2ndQuadrant.com>
	<535760.62572.qm@web111307.mail.gq1.yahoo.com>
	<AANLkTikGU9Dmo3bnh4vCn4L5q9u3efEH0-ZkwECzLwO8@mail.gmail.com>
In-Reply-To: <AANLkTikGU9Dmo3bnh4vCn4L5q9u3efEH0-ZkwECzLwO8@mail.gmail.com>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
Content-Transfer-Encoding: 7bit

On 2011-03-29 06:13, Merlin Moncure wrote:
> My own experience with MLC drives is that write cycle expectations are
> more or less as advertised. They do go down (hard), and have to be
> monitored. If you are writing a lot of data this can get pretty
> expensive although the cost dynamics are getting better and better for
> flash. I have no idea what would be precisely prudent, but maybe some
> good monitoring tools and phased obsolescence at around 80% duty cycle
> might not be a bad starting point.  With hard drives, you can kinda
> wait for em to pop and swap em in -- this is NOT a good idea for flash
> raid volumes.
What do you mean by "hard", I have some in our setup, but
havent seen anyting "hard" just yet. Based on report on the net
they seem to slow down writes to "next to nothing" when they
get used but that seems to be more gracefully than old
rotating drives..  can you elaborate a bit more?

Jesper

-- 
Jesper