Seagate ST3400755FC Performance characteristics, Internal drive characteristics, Seek performance

Models: ST3400755FC ST3300955FC

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4.0Performance characteristics

This section provides detailed information concerning performance-related characteristics and features of Cheetah NS FC drives.

4.1Internal drive characteristics

 

ST3400755FC

ST3300955FC

 

Drive capacity*

400.0

300

Gbytes (formatted, rounded off value)

Read/write data heads

8

4

 

Tracks per surface (total)

92,200

92,200

Tracks (user accessible)

Tracks per inch

155,000

155,000

TPI

Peak bits per inch

979k

979k

BPI

Areal density

151.7

151.7

Gbits/inch2

Internal data rate

725 to 1,211

725 to 1,211

Mbits/sec (variable with zone)

Disc rotation speed

10k

10k

rpm

Avg rotational latency

2.98

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.

4.2Seek performance

See Section 9.5, "FC-AL physical interface" on page 61 and the Fibre Channel Interface Manual (part number 77767496) for additional timing details.

4.2.1Access time

Not including controller overhead1,2(msec)

 

 

Read

Write

Average

Typical

3.9

4.2

Single track

Typical

0.35

0.52

Full stroke

Typical

6.8

7.5

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.

Cheetah NS FC Product Manual, Rev. A

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Seagate ST3400755FC manual Performance characteristics, Internal drive characteristics, Seek performance, Access time