Automatic Storage Management (ASM) provides a simple way to manage Oracle database files across disk storage. ASM uses disk groups and metadata to distribute data extents across disks for redundancy. Rebalancing operations redistribute extents to maintain even distribution as disks are added or removed, and the estimated time for rebalancing can be found in V$ASM_OPERATION. ASM supports different redundancy levels including external, normal, and high redundancy.
11. ASM Disk Groups and Disks Disk Group 1 Disk Group 2 Disk Group 3 Disk 1 Disk 4 Disk 2 Disk 6 Disk 5 Disk 7 Disk 3
12. ASM Disk Groups and Disks Disk Group 1 Disk 1 Disk 4 Disk Group 2 Disk 2 Disk 5 Disk 6 Disk 7 Disk 3 Disk Group 3
13. ASM Disk Groups, Disks and Database Files Disk Group 1 Disk 1 Disk 4 Disk Group 2 Disk 2 Disk 5 Disk 6 Disk 7 Disk 3 Disk Group 3 File 1 File 2 File 3 File 4 File 5 File 5 File 6
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17. ASM Metadata Active Change Directory Continuing Operations Directory Template Directory Alias Directory Disk Directory File Directory Partner Status Table Metadata Header Free Space Table Allocation Table Disk Header Metadata Header
26. Extent Distribution 2 disks Disk 0 Disk 1 Metadata Metadata Data 0 2 4 6 8 10 12 14 1 3 5 7 9 11 13 15
27. Extent Distribution 4 disks Disk 0 Disk 1 Disk 2 Disk 3 Metadata Metadata Data 0 4 8 12 16 20 24 28 2 6 10 14 18 22 26 30 1 5 9 13 17 21 25 29 3 7 11 15 19 23 27 31
28. Extent Distribution 1 large disk - 1 small disk Disk 0 Disk 1 Metadata Metadata Data 0 1 3 4 6 7 9 10 2 5 8 11
29. Extent Distribution 1 large disk - 3 small disks Disk 1 Disk 2 Metadata Disk 0 Disk 4 Metadata Data 1 6 11 16 0 3 5 8 10 13 15 18 2 7 12 17 4 9 14 19
30. Extent Distribution 2 large disks - 2 small disks Disk 1 Disk 2 Metadata Disk 0 Disk 4 Metadata Data 3 9 15 21 0 2 6 8 12 14 18 20 1 4 7 10 5 11 17 23 13 16 19 22