Message-ID: <4E555AF5.4080202@2ndQuadrant.com>
Date: Wed, 24 Aug 2011 16:11:33 -0400
From: Greg Smith <greg@2ndQuadrant.com>
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To: pgsql-performance@postgresql.org
Subject: Re: Intel 320 SSD info
References: <4E552DCF.80802@boreham.org>
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	<4E5537C9.9080308@2ndQuadrant.com> <4E5537F6.3070105@boreham.org>
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On 08/24/2011 01:42 PM, David Boreham wrote:
> On 8/24/2011 11:41 AM, Greg Smith wrote:
>>
>>
>> I've measured the performance of this drive from a couple of 
>> directions now, and it always comes out the same.  For PostgreSQL, 
>> reading or writing 8K blocks, I'm seeing completely random workloads 
>> hit a worst-case of 20MB/s; that's just over 2500 IOPS.  It's quite 
>> possible that number can go lower under pressure of things like 
>> internal drive garbage collection however, which I believe is going 
>> into the 600 IOPS figure.  I haven't tried to force that yet--drive 
>> is too useful to me to try and burn it out doing tests like that at 
>> the moment.
>
> I hope someone from Intel is reading -- it would be well worth their 
> while to just send you a few drives,
> since you are set up to perform the right test, and can provide 
> impartial results.

Don't worry, they are.  With the big firmware bug in the 320 series 
lingering over things, it wasn't really worth wandering down that road 
yet until this week.  Now that they can ship me drives that are expected 
to work, I can pick back up work on performance testing them.

-- 
Greg Smith   2ndQuadrant US    greg@2ndQuadrant.com   Baltimore, MD
PostgreSQL Training, Services, and 24x7 Support  www.2ndQuadrant.us