Re: [Q]: Raid 0 or Raid 5 for DATA tablespaces : Which is best ?

Jerome Grandjanny wrote:
>
> Hello all Oracle gurus,
>
> May be this question has been already discussed.
>
> I'am in charge of designing a disk layout for a new database.
>
> I need to decide wether I use RAID 0 (stripping) or RAID 5 for
> the tablespaces containing the data and the indexes.
>
> The database must run 24/24-7/7.
>
> In some books about Oracle, I read that using RAID 5 is not always a
> good choice for data (possible performance problems during write
> operations).
>
> In the other hand, in case of a disk crash, a hot plugging RAID 5
> system can offer a non-stop recovery mechanism.
>
> Please, let me know your opinion, your experience, ...
> Any advice welcome.
> Thanks.
> Sincerely,
> Jerome.

For 24 hours a day and 7 days a week availability RAID0 is not an option. RAID5/RAID7 seems the mostly commonly used configuration. Mirroring is another option, but not cost-effective for larger databases, say 16 Gig and above. As George Dau has suggested (good one) you can use combinations, this leads to administrative overheads; depends on the available in-house UNIX skil.

RAID5/RAID7 configuration is simple, hassle free, cost-effective and with acceptable performance level. Write penalty is not significantly higher than RAID0 with the usual 7-1(data-parity) configuration. You can cut this down further by going for 15-1 (if possible) configuration, of course this depends on the failure rate of your hard disks.

Thanks. Received on Tue Aug 12 1997 - 00:00:00 CDT