Seagate Cheetah ST3146854, Руководство пользователя

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Cheetah 15K.4 SCSI Product Manual, Rev. D 9
3.3 Performance
• Supports industry standard Ultra320 SCSI interface
• Programmable multi-segmentable cache buffer (see Section 4.5)
• 15k RPM spindle. Average latency = 2.0 msec
• Command queuing of up to 64 commands
• Background processing of queue
• Supports start and stop commands (spindle stops spinning)
3.4 Reliability
• 1,400,000 hour MTBF
• Increased LSI circuitry integration
• 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 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.
3.5.1 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 Interface Product 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
ST336754 ST373454 ST3146854
Decimal Hex Decimal Hex Decimal Hex
512 71,687,372 445DCCC 143,374,744 88BB998 286,749,488 11177330
514 70,512,692 433F034 141,025,384 867E068 282,050,768 10CFC0D0
520 70,197,546 42F212A 140,395,092 85E4254 280,790,184 10BC84A8
522 68,914,176 41B8C00 137,834,496 8373000 275,656,704 106E3000
524 68,766,592 4194B80 137,577,184 83342E0 275,154,368 106685C0
528 68,165,733 4102065 136,331,467 82040CB 272,662,935 10408197