Review the usable disk capacity available for Oracle Database Appliance X6-2S, X6-2M, and X6-2L and how capacity is derived.
Oracle Database Appliance X6-2S, X6-2M, and X6-2L use 3.2 TB raw NVMe flash Solid-State Drives. The usable data capacity in the following tables varies because it is derived by converting terabytes reported in decimal (based on 1 kilobyte equals 1,000 bytes) into terabytes reported in binary (based on 1 kilobyte equals 1,024 bytes) and splitting the usable capacity into Oracle Automatic Storage Management (Oracle ASM) disk groups.
In summary, each NVMe SSD usable storage is approximately 2.91TB. This is calculated by the storage usable capacity of the drive converted to TB. 3.2 TB divided by 1.0244= 2.91TB.
Usable Disk Capacity on Oracle Database Appliance X6-2S and X6-2M
The following table provides the approximate amount of usable space for the Oracle Database Appliance X6-2S and X6-2M.
Table B-2 Usable Disk Capacity on Oracle Database Appliance X6-2S and X6-2M
| Description | Sizing for X6-2S with 2 NVMe Drives | Sizing for X6-2S with 4 NVMe Drives |
|---|---|---|
| Number of NVMe Drives |
2 |
4 |
|
Total Usable Space |
5.8TB |
11.6TB |
|
Total Usable Normal (Double Mirror) Oracle ASM Redundancy |
2.9TB |
5.8TB |
|
DATA Disk Group (90% Usable) |
2.6TB |
5.2TB |
|
RECO Disk Group (10% Usable) |
0.3TB |
0.6TB |
|
Total Usable High (Triple Mirror) Oracle ASM Redundancy |
NA. Triple mirroring is not applicable for the X6-2S. |
3.9TB |
|
DATA Disk Group (90% Uusable) |
NA. Triple mirroring is not applicable for the X6-2S. |
3.5TB |
|
RECO Disk Group (10% Uusable) |
NA. Triple mirroring is not applicable for the X6-2S. |
0.4TB |
Usable Disk Capacity on Oracle Database Appliance X6-2L
Based on the calculations of the capacity of the storage drives and including the reserved space for redundancy, the following table reflects the approximate usable storage of the Oracle Database Appliance X6-2L.
Table B-3 Usable Storage on Oracle Database Appliance X6-2L
| Description | Sizing for X6-2L with 6 NVMe Drives | Sizing for X6-2L with 9 NVMe Drives |
|---|---|---|
| Number of NVMe Drives |
6 |
9 |
|
Total Usable Space |
17.4TB |
26.1TB |
|
Reserved Space Normal Redundancy |
2.9TB |
2.9TB |
|
Total Usable Normal (Double Mirror) Oracle ASM Redundancy |
7.2TB |
11.6TB |
|
DATA Disk Group (90% Usable) |
6.5TB |
10.4TB |
|
RECO Disk Group (10% Usable) |
0.7TB |
1.2TB |
|
Reserved Space High Redundancy |
5.8TB |
5.8TB |
|
Total Usable High (Triple Mirror) Oracle ASM Redundancy |
3.8TB |
6.8TB |
|
DATA Disk Group (90% Usable) |
3.4TB |
6.1TB |
|
RECO Disk Group (10% Usable) |
0.4TB |
0.7TB |
The Reserved Space values represent the amount of storage required to maintain full redundancy in case of disk failure.
Oracle ASM Calculations
When Oracle ASM calculates usable Free Space, it determines the amount of space to reserve in the case of a disk failure. For Oracle Database Appliance X6-2S or X6-2M with 2 or 4 NVMe drives, this reserved space is not required. When you query Oracle ASM or Oracle Database Appliance commands to view the amount of storage available, the usable_File_MB value may report a negative number.
Table B-4 Oracle ASM Calculations
|
Number of Drives |
Redundancy |
Total_MB |
Free_MB |
Req_mir_free_MB |
Usable_file_MB |
Name |
|
2 |
NORMAL |
4894016 |
4893372 |
2441888 |
1220644 |
DATA/ |
|
4 |
NORMAL |
1231176 |
1230996 |
610468 |
305150 |
RECO/ |
Note:
Note: 1TB = MB divided by 10242The following table describes how capacity terms are defined by Oracle ASM and Oracle Database Appliance.
Table B-5 Definition of Terminology
|
Term |
Oracle ASM Definition |
Oracle Database Appliance Definition |
Total_MB |
Size of the disk group in MB |
Total usable storage. For example, for 2 NVMe drives, total usable storage is 5.8TB. |
Free_MB |
Free space in the disk group in MB, without regard to redundancy. |
Total usable storage after formatting to Oracle ASM disk groups. For example, for 2 NVMe drives, total usable storage is 5.8TB. |
Req_mir_free_MB |
Amount of space that must be available in the disk group to restore full redundancy after the worst failure that can be tolerated by the disk group. |
Usable space required to restore full redundancy. In the case of X6-2S and X6-2M, this storage is not required to be reserved. When storage is consumed higher than the |
Usable_file_MB |
Amount of free space, adjusted for mirroring, that is available for new files. |
Total usable space taking into consideration the mirroring level. Oracle ASM also calculates the amount of space required |
Parent topic: Storage on Oracle Database Appliance