Message-ID: <4D9A6FB6.2000702@2ndQuadrant.com>
Date: Mon, 04 Apr 2011 21:26:14 -0400
From: Greg Smith <greg@2ndQuadrant.com>
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To: pgsql-performance@postgresql.org
Subject: Re: Intel SSDs that may not suck
References: <4D90EDB6.2080609@2ndQuadrant.com>
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On 03/28/2011 04:21 PM, Greg Smith wrote:
> Today is the launch of Intel's 3rd generation SSD line, the 320 
> series.  And they've finally produced a cheap consumer product that 
> may be useful for databases, too!  They've put 6 small capacitors onto 
> the board and added logic to flush the write cache if the power drops.

I decided a while ago that I wasn't going to buy a personal SSD until I 
could get one without a volatile write cache for less than what a 
battery-backed caching controller costs.  That seemed the really 
disruptive technology point for the sort of database use I worry about.  
According to 
http://www.newegg.com/Product/Product.aspx?Item=N82E16820167050 that 
point was today, with the new 120GB drives now selling for $240.  UPS 
willing, later this week I should have one of those here for testing.

A pair of those mirrored with software RAID-1 runs $480 for 120GB.  LSI 
MegaRAID 9260-4i with 512MB cache is $330, ditto 3ware 9750-4i.  Battery 
backup runs $135 to $180 depending on model; let's call it $150.  Decent 
"enterprise" hard drive without RAID-incompatible firmware, $90 for 
500GB, need two of them.  That's $660 total for 500GB of storage.

If you really don't need more than 120GB of storage, but do care about 
random I/O speed, this is a pretty easy decision now--presuming the 
drive holds up to claims.  As the claims are reasonable relative to the 
engineering that went into the drive now, that may actually be the case.

-- 
Greg Smith   2ndQuadrant US    greg@2ndQuadrant.com   Baltimore, MD
PostgreSQL Training, Services, and 24x7 Support  www.2ndQuadrant.us
"PostgreSQL 9.0 High Performance": http://www.2ndQuadrant.com/books