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To: pgsql-performance@postgresql.org
From: George Neuner <gneuner2@comcast.net>
Subject: Re: Why HDD performance is better than SSD in this case
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On Wed, 18 Jul 2018 09:46:32 +0200, Fabio Pardi <f.pardi@portavita.eu>
wrote:

> RAID 0 to store production data should never be used. Never a good 
> idea, in my opinion.

RAID 0  by itself  should never be used.  Combined with other RAID 
levels, it can boost performance without sacrificing reliability.
https://en.wikipedia.org/wiki/Nested_RAID_levels


Personally, I don't like RAID 0 + ? schemes because they use too many 
disks (with associated reliability issues).  The required performance 
usually can be achieved in other ways.  But YMMV.
George