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andrewl41
15 Feb 2007, 12:24pm
Hi guys,

I've been trawling the web for information, trying to decide the best HDD configuration to go for for one of my servers and the most useful infromation seems to be in here, so I'd like to pose my questions to the forum directly in the hope of getting some expert opinion.

The scenario: I have a database backed application running on a server, this application writes extreamly intensivly to the database with little restbite, as well as dumping a lot of logging information. Obviously then it is write sensative.

I'm looking to improve the performance of the systems and as IO is the obvious bottle neck, and given that the quantity of writes cannot be reduced, I'm looking at the disks first to try and improve performance.

If there a RAID configuation available that will actually improve percieved disk write speed? I'm assuming a decent controler with a large amount of cache will help but what options should I be considering?

Many thanks in advance for any help you can provide.

Andrew
Timsey
16 Feb 2007, 4:16pm
You could look at RAID0 which is optimised for performance, but you'll want to make sure you have good backups. Also, you can add RAID1 to a RAID0 set for redundancy RAID 0+1
Thrax
16 Feb 2007, 4:17pm
Read up on RAID10 and RAID30.
primesuspect
16 Feb 2007, 4:43pm
You can't really go much better than RAID 10 using a really good caching SCSI RAID controller and Ultra320/15KRPM disks.
Madball
16 Feb 2007, 5:47pm
What ever happened to Tex? He would be all over this post. Haven't seen him in quite awhile.
andrewl41
19 Feb 2007, 10:15am
Hi guys,

I've been doing a fair bit of reading over the last week or so and my conclusions seem to match what everyone has said... RAID 0 would probably be about as quick as you can go but RAID 01 or 10 will be just about there and offer the redundency that is always desirable, probably with 6 disks as and as space isn't an issue, with three mirrors.

Our company has a policy of buying Dell servers which will ship with a Perc 5i controllers I think, with 256Mb of cache. Are these decent controlers, or would I be see a further improvement getting a different controler?

Thanks very much for the advice, it's much appreciated.


Andrew
primesuspect
19 Feb 2007, 4:09pm
The PERCs are very nice controllers. They're just re-branded high end controllers, but they come with dell software and support.