Seagate Cheetah NS SAS ST3400755SS, Product Manual

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Cheetah NS SAS Product Manual, Rev. B 11
4.0 Performance characteristics
This section provides detailed information concerning performance-related characteristics and features of
Cheetah NS SAS drives.
4.1 Internal drive characteristics
ST3400755SS
Drive capacity 400.0 Gbytes (formatted, rounded off value)
*
Read/write data heads 8
Tracks per surface (total) 92,200 Tracks (user accessible)
Tracks per inch 155,000 TPI
Peak bits per inch 979k BPI
Areal Density 151.7 Gbits/inch
2
Internal data rate 725 to 1,211 Mbits/sec (variable with zone)
Disk rotation speed 10k rpm
Avg rotational latency 2.98 msec
*One Gbyte equals one billion bytes when referring to hard drive capacity. Accessible capacity may vary depending on operating environment
and formatting.
4.2 Seek performance
See Section 9.4.1, "SAS physical interface" on page 51 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 3.9 4.2
Single track Typical 0.35 0.52
Full stroke Typical 6.8 7.5