Seagate ST9146802SS ユーザーズマニュアル

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Savvio 10K.2 SAS Product Manual, Rev. D
9
3.4
Reliability
• Annualized Failure Rate (AFR) or 0.55%
• Mean time between failures (MTBF) of 1,600,000 hours
• Balanced low mass rotary voice coil actuator
• Incorporates industry-standard Self-Monitoring Analysis and Reporting Technology (S.M.A.R.T.)
• 5-year warranty
3.5
Formatted capacities
Standard OEM models are formatted to 512 bytes per block. The block size is selectable at format time and 
must be a multiple of 4 bytes. Users having the necessary equipment may modify the data block size before 
issuing a format command and obtain different formatted capacities than those listed.
To provide a stable target capacity environment and at the same time provide users with flexibility if they 
choose, Seagate recommends product planning in one of two modes:
1.
Seagate designs specify capacity points at certain block sizes that Seagate guarantees current and future 
products will meet. We recommend customers use this capacity in their project planning, as it ensures a 
stable operating point with backward and forward compatibility from generation to generation. The current 
guaranteed operating points for this product are: 
2.
Seagate drives also may be used at the maximum available capacity at a given block size, but the excess 
capacity above the guaranteed level will vary between other drive families and from generation to genera-
tion, depending on how each block size actually formats out for zone frequencies and splits over servo 
bursts. This added capacity potential may range from 0.1 to 1.3 percent above the guaranteed capacities 
listed above. Using the drives in this manner gives the absolute maximum capacity potential, but the user 
must determine if the extra capacity potential is useful, or whether their assurance of backward and for-
ward compatibility takes precedence.
3.6
Programmable drive capacity
Using the Mode Select command, the drive can change its capacity to something less than maximum. See the 
Mode Select (6) parameter list table in the SAS Interface Manual, part number 100293071. A value of zero in 
the Number of Blocks field indicates that the drive will not change the capacity it is currently formatted to have. 
A number other than zero and less than the maximum number of LBAs in the Number of Blocks field changes 
the total drive capacity to the value in the Number of Blocks field. A value greater than the maximum number of 
LBAs is rounded down to the maximum capacity.
3.7
Factory-installed accessories
OEM standard drives are shipped with the Savvio 10K.2 SAS Installation Guide (part number 100384761).
 Capacity (Blocks)
Sector Size
ST9146802SS
ST973402SS
Decimal
Hex
Decimal
Hex
512
286749488
11177330h
143374744
88BB998h
520
280790192
10BC84B0h
140395096
85E4258h
528
272662936
10408198h
136331468
82040CCh