Recently ST9900 introduced concept of RAID concatenation. The benefit is to achieve the better performance
in the backend. It allows striping the data across more disks. The disadvantage could be chances of more
LDEV blockade if two or more HDDs are blocked (depends on RAID level used)
With "RAID5 concatenation"on V06 code and higher, you can stripe across either two or four RAID5 7+1
parity groups (i.e. up to 32 drives).
For both the ST 9985 V and ST 9990 V, the following RAID is supported:
RAID1 (2D + 2
M
)
RAID5 (3D + 1P)
RAID6 (6D +2P)
RAID5 (7D+1P)
RAID1 (4D+4M)
There is a maximum of 40 Global Spares. However the configuration tool will not let you configure 40 spares;
it will only allow you to configure 16 spares. So configure 16 spares and order and order extra data drives and
convert them to spares by reconfiguring the system.
Table 2-1
Disk Drive Specifications
Parameter
72 GB (15
krpm)
DKS2C-K72
FC
146 GB (15 krpm)
DKS2D-K146FC
Formatted capacity (GB)
71.50
143.76
Revolution speed (rpm)
15,000
15,000
Platter diameter
2.5 inches
2.5 inches
Physical tracks per physical
cylinder
(user area) (number of heads)
8
8
Physical disk platters (user area)
(numbers of disks)
4
4
Sector length (byte)
520 (512)
520 (512)
Seek time (ms) (read/write)
MIN
0.4 / 0.6
0.4 / 0.6
MAX
6.7 / 7.1
6.7 / 7.1
AVE
3.8 / 4.2
3.8 / 4.1
Average latency time (ms)
2.01
2.01
Internal data transfer rate
(MB/sec)
74.5 to 111.4
76.13 to 113.78
Max. interface data transfer rate
(MB/sec)
200
200
Parameter
300 GB (15krpm)
DKS2E=K300FC
Formatted capacity (GB)
288.20
Revolution speed (rpm)
15,000
Platter diameter
N/A
Just the Facts
October 2007
43
Sun Confidential – For Internal Use and Authorized Partner Use Only
