Seagate ES.2 FC ユーザーズマニュアル

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Barracuda ES.2 FC Product Manual, Rev. B
9
3.3
Performance
• Programmable multi-segmentable cache buffer 
• 800 Mbytes/sec maximum instantaneous data transfers
• 7,200 RPM spindle. Average latency = 4.16 msec
• Command queuing of up to
 
128 commands
• Background processing of queue
• Supports start and stop commands (spindle stops spinning)
• Adaptive seek velocity; improved seek performance
3.4
Reliability
• Annualized Failure Rate (AFR) of 0.73%
• Mean Time Between Failures (MTBF) of 1,200,000 hours
• 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 sector size is selectable at format time. 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 sector 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 sector size, but the excess 
capacity above the guaranteed level will vary between 10K and 15K families and from generation to gener-
ation, depending on how each sector 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 Parameter List table in the SCSI Commands Reference Manual. Refer to the Parameter list block 
descriptor number of blocks field. A value of zero in the number of blocks field indicates that the drive shall not 
Sector Size
ST31000640FC
Decimal
512
1,953,525,168
520
1,923,076,930
524
1,882,972,562
528
1,876,331,330