Barracuda ATA III Family Product Manual, Rev. B
7
1.4 Physical characteristics
1.5 Seek time
Seek measurements are taken with nominal power at 25°C ambient
temperature. All times are measured using drive diagnostics. The spec-
ifications in the table below are defined as follows:
•
Track-to-track seek time is an average of all possible single-track
seeks in both directions.
•
Average seek time is a true statistical random average of at least 5,000
measurements of seeks between random tracks, less overhead.
•
Full-stroke seek time is one-half the time needed to seek from the first
data cylinder to the maximum data cylinder and back to the first data
cylinder. The full-stroke typical value is determined by averaging 100
full-stroke seeks in both directions.
Note. These drives are designed to consistently meet the seek times rep-
resented in this manual. Physical seeks, regardless of mode (such as
track-to-track and average) are expected to meet or exceed the noted
values. However, due to the manner in which these drives are format-
ted, benchmark tests that include command overhead or measure
logical seeks may produce results that vary from these specifications.
Drive Specification
ST340824A, ST330620A,
ST320414A, ST315310A,
ST310215A
Maximum height (mm)
(inches)
26.1
1.028
Maximum width
(mm)
(inches)
101.8
4.020
Maximum length (mm)
(inches)
147.0
5.75
Typical weight
(grams)
(pounds)
554
1.2
Typical seek times (msec)
Read
Write
Track-to-track
1.2
2.0
Average
8.5
9.5
Full-stroke (max)
22.0
24.0
Average latency: 4.16 msec
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