From: David Boreham <david_list@boreham.org>
To: pgsql-performance@postgresql.org
Subject: Re: Intel 320 SSD info
Date: Wed, 24 Aug 2011 11:25:27 -0600
Message-ID: <4E553407.6010608@boreham.org> (raw)
In-Reply-To: <1314206629.63488.YahooMailNeo@web111301.mail.gq1.yahoo.com>
References: <4E552DCF.80802@boreham.org>
<1314206629.63488.YahooMailNeo@web111301.mail.gq1.yahoo.com>
On 8/24/2011 11:23 AM, Andy wrote:
> According to the specs for database storage:
>
> "Random 4KB arites: Up to 600 IOPS"
>
> Is that for real? 600 IOPS is *atrociously terrible* for an SSD. Not
> much faster than mechanical disks.
>
>
The underlying (Flash block) write rate really is terrible (and slower
than most rotating disks).
The trick with SSD is that firmware performs all kinds of stunts to make
the performance seen
by the OS much higher (most of the time !). This is akin to write-back
caching in a raid controller,
for example, where much higher write rates than the physical drives
support are achievable.
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To: pgsql-performance@postgresql.org
Cc: david_list@boreham.org
Subject: Re: Intel 320 SSD info
In-Reply-To: <4E553407.6010608@boreham.org>
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