Re: Configuring Oracle on RAID 5

In article <Zfzr6.2592$CW3.267736_at_paloalto-snr1.gtei.net>, none_at_nospam.com says...
> Maybe the bozos that were explaining RAID to you were just salesman.
>
> But, RAID 5 can work, and is used on major databases.
>
> The problem is the amount of writes that are required and associated.
>
> The entire problem is not RAID, it is a transaction per second you need to
> sustain.
>
> So, you need to solve for transactions per second that your DB needs to
> maintain. There is a formula that Compaq uses to determine the amount of
> drives needed in a RAID 5 array to meet your transactions per second rate
> due to the amount of write operations needed to perform a transaction with
> RAID 5 due to overhead.
>
> It may take 80 hardrives in a RAID 5 array to meet your transaction rate,
> but it is possible, that is the problem with RAID 5, the amount of write
> operations needed to stripe the information across the array, it isn't
> necessary that they can't do it, it is just the formula has to be crunched
> to meet the DB requirements of sustained transaction rate. Then, it will
> tell you how many drives you need in a RAID 5 array to meet this rate.
>
> Keith
>

It would probably take half that in raid 0 + 1 and you would not pay the performance penalty when you lose a disk.

Liz Received on Wed Mar 14 2001 - 15:17:35 CST