Specifications

SAP R/3 Sizing and Installation Planning 149
5.4.2 Oracle Database Installation Planning
5.4.2.1 Distribution of SAP Software using RAID
It is recommended that a minimum of three logical disk volumes are used to
separate the online redo logs, offline redo logs and database files because of
safety and performance issues.
The online redo logs(\ORACLE\<SAPSID>\origlogA and
\ORACLE\<SAPSID>\origlogB) and the offline redo logs
(\ORACLE\<SAPSID>\saparch) must reside on different logical disk volumes
using RAID 1(Disk Mirroring).
In SAP systems with a very high data throughput, the directories origlogA and
origlogB should reside on different disks for performance reasons. In that case,
you would need four logical disks.
The data files (\ORACLE\<SAPSID>\sapdata1 ... \ORACLE\<SAPSID>\sapdata5)
should be located on a logical disk volume using RAID 5(distributed parity
checking).
5.4.2.2 Distributing the SAP Software Using Separate Disks
For safety reasons, always distribute the following directories to separate physical
disks:
1. The database log files:
\ORACLE\<SAPSID>\origlogA
\ORACLE\<SAPSID>\origlogB
2. The mirrored database log files:
\ORACLE\<SAPSID>\mirrlogA
\ORACLE\<SAPSID>\mirrlogB
3. The archived database log files:
\ORACLE\<SAPSID>\saparch
4. All Oracle data file directories:
sapdata1 - sapdata<N>
To distribute the directories in this way, you need at least four disks. The
remaining directories can be distributed to any of these four disks:
\USR\SAP
\USR\SAP\TRANS
\ORANT
\ORACLE\<SAPSID>\sapreorg
\ORACLE\<SAPSID>\saptrace
\ORACLE\<SAPSID>\sapbackup
\ORACLE\<SAPSID>\sapcheck
On Netfinity SAP systems with a high data throughput we recommend that you
distribute the following log directories in different disks for better performance:
\ORACLE\<SAPSID>\origlogA
\ORACLE\<SAPSID>\mirrlogA
\ORACLE\<SAPSID>\origlogB
\ORACLE\<SAPSID>\mirrlogB