Full Stroke Seek; Average Latency - IBM DDRS-39130 - Ultrastar 9.1 GB Hard Drive Specifications

3.4.2.2 Full Stroke Seek

Figure 5. Full Stroke Seek Time
Function
Read [ msec]
Write [ msec]
Full stroke seek is measured as the average of 1000 full stroke seeks with a random head switch from both
directions (inward and outward).
3.4.2.3 Cylinder Switch Time (Cylinder Skew)
Figure 6. Cylinder Skew
Cylinder Skew
A cylinder switch time is defined as the amount of time required by the fixed disk access the next sequential
block after reading the last sector in the current cylinder.
The measured method is given in 3.4.7, "Throughput" on page 15.
3.4.2.4 Head Switch Time (Head Skew)
Figure 7. Head Skew
Head Skew

3.4.2.5 Average Latency

Figure 8. Latency Time
Rotation
7200 [ R P M ]
12
O E M Spec. of DDRS-3xxxx
Typical
15.0
15.8
Time for a revolution
8.33 [ msec]
Max.
16.0
16.8
Typical
2.6 [ msec]
Typical
1.6 [ msec]
Average Latency
4.17 [ msec]