Seagate Cheetah 15K.6 SAS, Руководство по эксплуатации продукта

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Cheetah 15K.6 SAS Product Manual, Rev. A 11
4.0 Performance characteristics
This section provides detailed information concerning performance-related characteristics and features of
Cheetah drives.
4.1 Internal drive characteristics
ST3450856SS ST3300656SS ST3146356SS
Drive capacity 450 300 146 Gbytes (formatted, rounded off value)
*,**
Read/write data heads 8 6 3
Tracks per inch 150,000 150,000 150,000 TPI
Peak bits per inch 1,100 1,100 1,100 KBPI
Areal Density 165 165 165 Gbits/inch
2
Internal data rate 1.95 1.95 1.95 Gbits/sec (max)
disk rotation speed 15k 15k 15k RPM
Avg rotational latency 2.0 2.0 2.0 msec
*One Gbyte equals one billion bytes when referring to hard drive capacity. Accessible capacity may vary depending on operating environment
and formatting.
**Rounded off value.
4.2 Seek time
See Section 9.4.1, "SAS physical interface" on page 59 and the SAS Interface Manual (part number
100293071) for additional timing details.
4.2.1 Access time
Not Including controller overhead
1
,
2
(msec)
1. Typical access times are measured under nominal conditions of temperature, voltage, and
horizontal orientation as measured on a representative sample of drives.
2. Access to data = access time + latency time.
Read Write
Average Typical 3.4 3.9
Single track Typical 0.20 0.44
Full stroke Typical 6.43 7.12