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Message-ID: <4E00FE4B.3030204@gmail.com>
Date: Tue, 21 Jun 2011 22:25:47 +0200
From: Yeb Havinga <yebhavinga@gmail.com>
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To: Greg Smith <greg@2ndQuadrant.com>
CC: Florian Weimer <fweimer@bfk.de>, pgsql-performance@postgresql.org
Subject: Re: Contemplating SSD Hardware RAID
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On 2011-06-21 22:10, Yeb Havinga wrote:
>
>
> There's some info burried in 
> http://archives.postgresql.org/pgsql-performance/2011-03/msg00350.php 
> where two Vertex 2 pro's are compared; the first has been really 
> hammered with pgbench, the second had a few months duty in a 
> workstation. The raw value of SSD Available Reserved Space seems to be 
> a good candidate to watch to go to 0, since the pgbenched-drive has 
> 16GB left and the workstation disk 17GB. Would be cool to graph with 
> e.g. symon (http://i.imgur.com/T4NAq.png)
>

I forgot to mention that both newest firmware of the drives as well as 
svn versions of smartmontools are advisable, before figuring out what 
all those strange values mean. It's too bad however that OCZ doesn't let 
the user choose which firmware to run (the tool always picks the 
newest), so after every upgrade it'll be a surprise what values are 
supported or if any of the values are reset or differently interpreted. 
Even when disks in production might not be upgraded eagerly, replacing a 
faulty drive means that one probably needs to be upgraded first and it 
would be nice to have a uniform smart value readout for the monitoring 
tools.

-- 
Yeb Havinga
http://www.mgrid.net/
Mastering Medical Data