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From: Craig Ringer <craig@2ndQuadrant.com>
To: Evgeny Shishkin <itparanoia@gmail.com>
Cc: Niels Kristian Schjødt <nielskristian@autouncle.com>
Cc: Jeff Janes <jeff.janes@gmail.com>
Cc: pgsql-performance@postgresql.org <pgsql-performance@postgresql.org>
Subject: Re: Do I have a hardware or a software problem?
Date: Wed, 12 Dec 2012 09:29:02 +0800
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On 12/12/2012 09:17 AM, Evgeny Shishkin wrote:
>
> Actually most of low-end SSDs don't do write caching, they do not have
> enough ram for that. Sandforce for example.
>
Or, worse, some of them do limited write caching but don't protect their
write cache from power loss. Instant data corruption!

I would be extremely reluctant to use low-end SSDs for a database server.

> If we are talking about dedicated machine for database with ssd
> drives, why would anybody don't by hardware raid for about 500-700$?
I'd want to consider whether the same money is better spent on faster,
higher quality SSDs with their own fast write caches.

-- 
 Craig Ringer                   http://www.2ndQuadrant.com/
 PostgreSQL Development, 24x7 Support, Training & Services

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