The outer track / inner track performance ratio is more like 40 percent. Recent example is 78MB/s outer and 44MB/s inner for the new Seagate 750MB drive (see http://www.storagereview.com for benchmark results)
- Luke
Msg is shrt cuz m on ma treo
-----Original Message-----
From: Jim Nasby [mailto:decibel@decibel.org]
Sent: Thursday, April 26, 2007 03:53 AM Eastern Standard Time
To: Pawel Gruszczynski
Cc: pgsql-performance@postgresql.org
Subject: Re: [PERFORM] What`s wrong with JFS configuration?
On Apr 25, 2007, at 8:51 AM, Pawel Gruszczynski wrote:
> where u6 stores Fedora Core 6 operating system, and u0 stores 3
> partitions with ext2, ext3 and jfs filesystem.
Keep in mind that drives have a faster data transfer rate at the
outer-edge than they do at the inner edge, so if you've got all 3
filesystems sitting on that array at the same time it's not a fair
test. I heard numbers on the impact of this a *long* time ago and I
think it was in the 10% range, but I could be remembering wrong.
You'll need to drop each filesystem and create the next one to get a
fair comparison.
--
Jim Nasby jim@nasby.net
EnterpriseDB http://enterprisedb.com 512.569.9461 (cell)
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