Re: NT Oracle database with RAID-5 hardware controller - Is it good?

On Thu, 23 Jul 1998 20:16:10 -0400, "fantail2" <fantail2_at_yahoo.com> wrote:

>I just heard that if you install an Oracle database on a COMPAQ ProLiant
>with a RAID-5 disk controller, the performance of the database is greatly
>reduced.
>
>Can someone can explain to me why?
>
>Thanks!
>
>
>
>
>

Basically because the performance of Raid 5 is not too good. A lot of the performance gains in Oracle are found by careful placing of tables across differing spindles, thereby ( in effect ) increasing the IO capacity available to your database. Raid 5 provides the user with what is effectively just one large disc, because of the striping that occurs inside that black box.

A far better way is to look at mirroring databases, and mirroring the controllers as well. That way you have trice the resources available to read the data, a slight hit on writing, and the security of that extra copy. And, of course, ensuring that you've got loads of memory too.

HTH Steve.

BTW the last I heard ( I'm mainly an Unix man ), it was advantageous to run the dataspaces on raw discs if you were after pure speed. The downside was that there was no way of backing the database up. Is this still the case? Received on Fri Jul 24 1998 - 11:20:48 CDT