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Message-ID: <4C617DE8.4030203@2ndquadrant.com>
Date: Tue, 10 Aug 2010 12:27:20 -0400
From: Greg Smith <greg@2ndquadrant.com>
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To: Jeff Davis <pgsql@j-davis.com>
CC: Scott Carey <scott@richrelevance.com>, Michael March <mmarch@gmail.com>,
	"pgsql-performance@postgresql.org" <pgsql-performance@postgresql.org>
Subject: Re: Completely un-tuned Postgresql benchmark results: SSD
	vs desktop HDD
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Jeff Davis wrote:
> Depending on which 256K you lose, you might as well lose your entire
> database.
>   

Let's be nice and assume that you only lose one 8K block because of the 
SSD write cache; that's not so bad, right?  Guess what--you could easily 
be the next lucky person who discovers the block corrupted is actually 
in the middle of the pg_class system catalog, where the list of tables 
in the database is at!  Enjoy getting your data back again with that 
piece missing.  It's really a fun time, I'll tell you that.

-- 
Greg Smith  2ndQuadrant US  Baltimore, MD
PostgreSQL Training, Services and Support
greg@2ndQuadrant.com   www.2ndQuadrant.us