Seagate ST3400755SS ユーザーズマニュアル
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.
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.
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.
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