Oracle Database Administration: The Essential Refe

Disk Layout

The more independent physical disks that can be dedicated to Oracle files, the better the I/O operation of the system is likely to be. Carefully planning the location of each Oracle file will yield significant improvements in the performance of the database. Use the following guidelines when laying out the disk subsystem:

• Allocate separate disks for data, redo logs, and archive files.

• Keep data and index segments for a given table in separate tablespaces, on separate disks.

• Use a separate disk for rollback segments.

• Keep the system tablespace on a separate disk or on a lightly used disk.

• Try to keep Oracle files on different disks from user filesystems.

An ideal disk layout might look like the layout shown in Table 11.2.

Table 11-2. Ideal Disk Layout

Disk	Contents
01 Controller A	Oracle software ($ORACLE_HOME ), control file 1
02 Controller A	SYSTEM tablespace
03 Controller A	DATA tablespace
04 Controller A	Redo log group 1, member 1 Redo log group 3, member 1
05 Controller A	Redo log group 2, member 1 Redo log group 4, member 1
06 Controller A	Redo log group 1, member 2 Redo log group 3, member 2
07 Controller A	Redo log group 2, member 2 Redo log group 4, member 2
08 Controller B	TOOLS tablespace
09 Controller B	TEMP tablespace, control file 2
10 Controller B	ROLLBACK tablespace
11 Controller B	INDEX tablespace
12 Controller B	Archivelog destination
13 Controller B	Application software
14 Controller B	User files, exports, etc.

Since this system ...