Re: RAID-5 vs. Disk Mirroring

We just made the decision to go with striping/mirroring instead of RAID-5. The RAID-5 performance issues were one major reason. The other reason is that in order to add drives to a RAID-5 array, the database needs to be exported, the new drives added, the disks reformatted, and the database imported (this is according to a SUN rdbms guru and our system admin; don't yell at me if this isn't correct). We did not want to take the downtime hit for the export/install/format/praying/import/praying.

My boss was not happy with the disk cost (1G = 500M mirrored), but he really did not like the downtime costs.

Hope this helps,

Mike Strong
Oracle DBA
Texas Instruments, Inc., Houston
(713) 274-3317

My opinions only.

In article 9ln_at_maverick.tad.eds.com, bob_at_latcost1.alaao.ats.eds.com (Bob Stewart) writes:
> BBAP (bbap_at_aol.com) wrote:
> : Does anyone have experience to share on either RAID-5 or Disk Mirroring.
> : We are trying to make a decision on a direction. The concern is which
> : method will ensure that data will be there (no loss is permited), while
> : not comprimising performance. Cost is not a consideration.
> ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
>
> When do I start?
>
> Seriously. If cost is not really a consideration, then don't bother
> looking at RAID5. RAID5 solutions are considerably slower on average
> than mirroring solutions. Both are reliable.
>
> Later.
> --
> Bob Stewart ASE
> (310) 335-7152 Air Transportation Division
> bob_at_latcost1.alaao.ats.eds.com
>
> I am definitely NOT speaking for EDS.
Received on Mon Jan 29 1996 - 00:00:00 CET