IBM DS8880 Series, Introduction And Planning Manual

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Table 40. RAID capacities for RAID 5 arrays (continued)
Drive size and
type
Total physical
capacity (GB)
per drive set
1, 2
Fixed block
(FB) or count
key data (CKD)
Effective capacity in GB
(number of extents)
2, 3
Rank with RAID 5 array
6 + P 7 + P
Notes:
1. Disk-drive and flash-drive sets contain 16 disk drives. Half-drive sets contain 8 disk
drives.
2. Physical capacities are in decimal gigabytes (GB) and terabytes (TB). One decimal GB is
1,000,000,000 bytes. One decimal TB is 1,000,000,000,000 bytes.
3. Rank capacities of DS8880 are different from rank capacities of earlier DS8000 storage
systems. This change in the number of extents must be planned for when you move or
migrate data to the DS8880.
RAID 6 array capacities for standard drive enclosures
The following table lists the RAID 6 array capacities for fully populated storage
enclosures.
Table 41. RAID capacities for RAID 6 arrays
Drive size and
type
Total physical
capacity (GB)
per drive set
1, 2
Fixed block (FB)
or count key
data (CKD)
Effective capacity in GB
(number of extents)
2, 3
Rank with RAID 6 array
5 + P + Q 6 + P + Q
300 GB disk
drives 4,800 FB 1,347.55
(1,255) 1,628.87
(1,517)
CKD 1,331.98
(1,408) 1,610.10
(1,702)
400 GB 2.5-in.
flash drives
(SSD) 6,400 FB 1,856.50
(1,729) 2,241.97
(2,088)
CKD 1,834.30
(1,939) 2,214.60
(2,341)
600 GB disk
drives 9,600 FB 2,750.93
(2,562) 3,318.94
(3,091)
CKD 2,718.82
(2,874) 3,279.80
(3,467)
800 GB 2.5-in.
flash drives
(SSD) 12,800 FB 3,750.58
(3,493) 4,521.53
(4,211)
CKD 3,706.45
(3,918) 4,467.98
(4,723)
1.2 TB disk
drives 19,200 FB 5,541.58
(5,161) 6,676.53
(6,218)
CKD 5,475.48
(5,788) 6,597.44
(6,974)
1.6 TB 2.5-in.
flash drives
(SSD) 25,600 FB 7,539.82
(7,022) 9,081.71
(8,458)
CKD 7,450.74
(7,876) 8,974.75
(9,487)
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DS8880 Introduction and Planning Guide