From: Joe Landman <landman@scalableinformatics.com>
To: xfs@oss.sgi.com
Subject: Re: A little RAID experiment
Date: Fri, 27 Apr 2012 11:28:53 -0400 [thread overview]
Message-ID: <4F9ABB35.4020806@scalableinformatics.com> (raw)
In-Reply-To: <CAAxjCExzLXGMw2O32kR8xGS6-EpfwfKm-zkM0Vy58bryWygZuQ@mail.gmail.com>
On 04/26/2012 04:53 AM, Stefan Ring wrote:
> I just want to stress that our machine with the SmartArray controller
> is not a cheap old dusty leftover, but a recently-bought (December
> 2011) not exactly cheap Blade server, and that’s all you get from HP.
We have an anecdote about something akin to this which happened 2 years
ago. A potential customer was testing a <insert large multi-letter
acronym brand name here> machine to run a specific set of software which
tightly coupled to its disks. Performance was terrible. Our partner
(the software vendor) contacted us and asked us to help. We'd suggested
that the partner loan them the machine they had bought from us 2 years
earlier (at the time) and try that.
Our 2 year old machine (actually 2 generations back at the time of test,
now 5 generations behind our current kit) wound up being more than an
order of magnitude faster than the (then) latest and greatest kit from
<insert large multi-letter acronym brand name here>.
The lesson is this. Latest and greatest doesn't mean fastest. Design,
and implementation matter. Brand names don't.
To this day, we still see machines being pushed out with PCIx technology
for networking, or disk, or ...
... and customers buy it up, for reasons that have little to do with
performance, suitability to the task, etc.
If you need performance, its important to focus some effort upon
locating systems/vendors capable of performing where you need them to
perform. Otherwise you may wind up with a warmed over web server with
some random card and a few "fast" disks tossed in.
I don't mean to be blunt, but this is basically what you were sold.
Note also, I see this in cluster file system bits all the time. We get
calls from people, who describe a design, and ask us for help making
them go fast. We discover that they've made some deep fundamental
design decisions very poorly (usually upon the basis of what <insert
large multi-letter acronym brand name here> told them were options), and
there was no way to get between point A (their per unit performance) and
point B (what they were hoping for as an aggregate system performance).
At the most basic level, your performance will be modulated by your
slowest performing part. You can put infinitely fast disks on a slow
controller, and your performance will be terrible. You can put slow
disks on a very fast controller, and you will likely have better luck.
/Hoping this lesson is not lost ...
--
Joseph Landman, Ph.D
Founder and CEO
Scalable Informatics Inc.
email: landman@scalableinformatics.com
web : http://scalableinformatics.com
http://scalableinformatics.com/sicluster
phone: +1 734 786 8423 x121
fax : +1 866 888 3112
cell : +1 734 612 4615
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next prev parent reply other threads:[~2012-04-27 15:28 UTC|newest]
Thread overview: 41+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-04-25 8:07 A little RAID experiment Stefan Ring
2012-04-25 14:17 ` Roger Willcocks
2012-04-25 16:23 ` Stefan Ring
2012-04-27 14:03 ` Stan Hoeppner
2012-04-26 8:53 ` Stefan Ring
2012-04-27 15:10 ` Stan Hoeppner
2012-04-27 15:28 ` Joe Landman [this message]
2012-04-28 4:42 ` Stan Hoeppner
2012-04-27 13:50 ` Stan Hoeppner
2012-05-01 10:46 ` Stefan Ring
2012-05-30 11:07 ` Stefan Ring
2012-05-31 1:30 ` Stan Hoeppner
2012-05-31 6:44 ` Stefan Ring
2012-07-16 19:57 ` Stefan Ring
2012-07-16 20:03 ` Stefan Ring
2012-07-16 20:05 ` Stefan Ring
2012-07-16 21:27 ` Stan Hoeppner
2012-07-16 21:58 ` Stefan Ring
2012-07-17 1:39 ` Stan Hoeppner
2012-07-17 5:26 ` Dave Chinner
2012-07-18 2:18 ` Stan Hoeppner
2012-07-18 6:44 ` Stefan Ring
2012-07-18 7:09 ` Stan Hoeppner
2012-07-18 7:22 ` Stefan Ring
2012-07-18 10:24 ` Stan Hoeppner
2012-07-18 12:32 ` Stefan Ring
2012-07-18 12:37 ` Stefan Ring
2012-07-19 3:08 ` Stan Hoeppner
2012-07-25 9:29 ` Stefan Ring
2012-07-25 10:00 ` Stan Hoeppner
2012-07-25 10:08 ` Stefan Ring
2012-07-25 11:00 ` Stan Hoeppner
2012-07-26 8:32 ` Dave Chinner
2012-09-11 16:37 ` Stefan Ring
2012-07-16 22:16 ` Stefan Ring
2012-10-10 14:57 ` Stefan Ring
2012-10-10 21:27 ` Dave Chinner
2012-10-10 22:01 ` Stefan Ring
2012-04-26 22:33 Richard Scobie
2012-04-27 21:30 ` Emmanuel Florac
2012-04-28 4:15 ` Richard Scobie
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