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Date: Wed, 10 Sep 2008 23:37:09 -0600
From: "Scott Marlowe" <scott.marlowe@gmail.com>
To: "James Mansion" <james@mansionfamily.plus.com>
Subject: Re: Effects of setting linux block device readahead size
Cc: "Greg Smith" <gsmith@gregsmith.com>,
	"Scott Carey" <scott@richrelevance.com>,
	"Mark Wong" <markwkm@gmail.com>, pgsql-performance@postgresql.org,
	"Gabrielle Roth" <gorthx@gmail.com>,
	"Selena Deckelmann" <selenamarie@gmail.com>
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On Wed, Sep 10, 2008 at 11:21 PM, James Mansion
<james@mansionfamily.plus.com> wrote:
> Greg Smith wrote:
>>
>> Average seek time:      4ms
>> Seeks/second:        250
>> Data read/seek:        1MB    (read-ahead number goes here)
>> Total read bandwidth:    250MB/s
>>
> Most spinning disks now are nearer to 100MB/s streaming.  You've talked
> yourself into twice that, random access!

The fastest cheetahs on this page hit 171MB/second:

http://www.seagate.com/www/en-us/products/servers/cheetah/

Are there any drives that have a faster sequential transfer rate out there?

Checked out hitachi's global storage site and they're fastest drive
seems just a tad slower.