Re: Oracle & Hardware RAID.

Raid 5 is not the best for Oracle as it is slow.

Here is the best choice, then rank downwards. A good oracle database is spread many disks as well as raid stripes.

Control Files:                     0, None, 0+1, 1
Redo Logs:                         0+1, 1, 5
System Tablespace:                 0+1, 1, 5
Sort Segment:                      0+1, 0, 1, None, 5
Rollback Segments:                 0+1, 1, None, 5
Indexed Read only Tables:          0+1, 1, None, 5
Sequencial Read Only Tables:       0+1, 5, None, 1
Write Intensive Tables:            0+1, 1, 5
Direct Load Intensive:             0+1, 1, 5, None
Data Protection:                   0+1, 1, 5
Cost:                              None, 0, 5, 1, 0+1

Idealy everything is spread accross many different disk configurations, how many and how deep is then cost adjusted. A nice setup to go by is this.

Redo logs:               Raid 1
Rollback Segments:       Raid 1 (0+1 if possible)
Indexes:                 Raid 5 (0+1 if possible)
Tables:                  Raid Raid 5 (0+1 if possible)
High insert tables:      Raid 1 / 0+1
Temporary Sorts:         Raid 0 (0+1 if possible)
Control File:            Spread among other disks
System Tablespace:       Raid 1 (0+1 if possible)
Exports:                 None, Raid 1
Archive Logs:            None, Raid 1

Nuff said.

In article <qF5D5.16295$L12.319956_at_news2-win.server.ntlworld.com>,   "graeme.lockhart" <graeme.lockhart_at_ntlworld.com> wrote:
> Although I am not really in the oracle field (NT Systems Manager) I
 hope
> someone can help with my query.
>
> We have a oracle database that currently resides on an aging external
> Clariion Raid cabinet. The DB is spread over several disks
 configured as
> RAID 10 and RAID 1. This set-up was chosen several years ago as the
 best
> set-up for oracle to run.
>
> Recently we purchased a new server with inernal RAID capabilities.
 As the
> exteranl cabinet is now quite old I would like to propose to our DBAs
 that
> the DB is installed on the internal RAID disks. However as there are
 only 8
> disks (although more capacity) I do not think it is practicle to pick
 the
> RAID levels as described above. I would like to configure the
 hardware RAID
> at level 5.
>
> What I would like to know is what is generally is the best RAID
> configuration for Oracle DBs is it striping/mirroring or can you use
> stripe/parity without major performance degradation
> Thanks in Advance
>
> Graeme Lockhart
>
>

--
Christopher R. Spence
OCP, MCP, MCSE, A+, RAPTOR, CNA


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