Seagate Cheetah 15K.5 SAS Series, Product Manual

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8 Cheetah 15K.5 SAS Product Manual, Rev. C
3.1 Standard features
Cheetah drives have the following standard features:
• 1.5 / 3 Gbit Serial Attached SCSI (SAS) interface
• Integrated dual port SAS controller supporting the SCSI protocol
• Support for SAS expanders and fanout adapters
• Firmware downloadable using the SAS interface
• 128 - deep task set (queue)
• Supports up to 32 initiators
• Jumperless configuration.
• User-selectable logical block size (512, 520, 524, or 528 bytes per logical block)
• Perpendicular recording technology
• Programmable logical block reallocation scheme
• Flawed logical block reallocation at format time
• Programmable auto write and read reallocation
• Reallocation of defects on command (Post Format)
• ECC maximum burst correction length of 320 bits
• No preventive maintenance or adjustments required
• Dedicated head landing zone
• Embedded servo design
• Automatic shipping lock
• Embedded servo design
• Self diagnostics performed when power is applied to the drive
• Zone bit recording (ZBR)
• Vertical, horizontal, or top down mounting
• Dynamic spindle brake
• 16 Mbyte data buffer (see Section 4.5).
• Drive Self Test (DST)
• Background Media Scan (BGMS)
• Power Save
3.2 Media description
The media used on the drive has an aluminum substrate coated with a thin film magnetic material, overcoated
with a proprietary protective layer for improved durability and environmental protection.
3.3 Performance
• Firmware-controlled multisegmented cache designed to dynamically adjust segments for enhanced system
performance.
• 300 Mbytes/sec maximum instantaneous data transfers.
• 15k RPM spindle. Average latency = 2.0 msec
• Background processing of queue
• Supports start and stop commands (spindle stops spinning)
• Adaptive seek velocity; improved seek performance