IBM DS8880 Series, Введение и руководство по планированию

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Table 41. RAID capacities for RAID 6 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 6 array
5 + P + Q 6 + P + Q
1.8 TB disk
drives 28,800 FB 8,331.16
(7,759) 10,034.12
(9,345)
CKD 8,232.14
(8,702) 9,915.08
(10,481)
4 TB disk drives
(Nearline) 64,000 FB 18,533.86
(17,261) 22,304.84
(20,773)
CKD 18,313.72
(19,359) 220,40.98
(23,299)
6 TB disk drives
(Nearline) 96,000 FB 27,896.89
(25,981) 33,573.76
(31,268)
CKD 27,566.60
(29,140) 33,176.41
(35,070)
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 10 array capacities for standard drive enclosures
The following table lists the RAID 10 array capacities for fully populated storage
enclosures.
Table 42. RAID capacities for RAID 10 arrays
Drive size and
type
Total physical
capacity (GB)
per drive set
1
Fixed block (FB)
or count key
data (CKD)
Effective capacity in GB
(number of extents)
2, 3
Rank with RAID 10 array
3 + 3 4 + 4
300 GB disk
drives 4,800 FB 813.90
(758) 1,097.36
(1,022)
CKD 804.10
(850) 1,084.12
(1,146)
400 2.5-in. GB
flash drives
(SSD) 6,400 FB 1,126.36
(1,049) 1,513.98
(1,410)
CKD 1,112.50
(1,176) 1,495.63
(1,581)
600 GB disk
drives 9,600 FB 1,676.11
(1,561) 2,247.34
(2,093)
CKD 1,656.46
(1,751) 2,220.27
(2,347)
Chapter 4. Storage system physical configuration
97