Hitachi Travelstar 5K320 HTS543232L9A300 Manual page 19

Mechanical positioning
4.4.2
4.4.2.1 Average seek time (including settling)
Command Type
Read
Write
Table 5. Mechanical positioning performance
Typical and Max. are defined throughout the performance specification as follows:
Typical Average of the drive population tested at nominal environmental and voltage conditions.
Max. Maximum value measured on any one drive over the full range of the environmental and
voltage conditions. (See section 6.1, "Environment" and section 6.2, "DC power
requirements" )
The seek time is measured from the start of motion of the actuator to the start of a reliable read or write
operation. A reliable read or write operation implies that error correction/recovery is not employed to
correct arrival problems. The Average Seek Time is measured as the weighted average of all possible
seek combinations.
Weighted Average = ––––––––––––––––––––––––––––
Where: max. = maximum seek length
n = seek length (1-to-max.)
Tn
in
Tn
out
4.4.2.2 Full stroke seek
Command Type
Read
Write
Table 6. Full stroke seek time
Full stroke seek time in milliseconds is the average time of 1000 full stroke seeks.
4.4.2.3 Single track seek time (without command overhead, including
Command Type
Read
Write
Table 7. Single track seek time
Single track seek is measured as the average of one (1) single track seek from every track in both
directions (inward and outward).
4.4.2.4 Average latency
Rotational Speed
(RPM)
5400
Table 8. Latency time
Typical (ms)
max.
 (max. + 1 – n)(Tn
+ Tn
in
n=1
(max. + 1)(max)
= inward measured seek time for an n-track seek
= outward measured seek time for an n-track seek
Typical (ms)
20.0
21.0
settling)
Time for one revolution
(ms)
11.1
12
13
)
out
Max. (ms)
25.0
26.0
Typical (ms)
1.0
1.1
Average Latency
(ms)
5.5
19
5K320 SATA OEM Specification
Max. (ms)
14
15
Maximum (ms)
2.0
2.2