Hitachi HDS725050KLA360 Specifications - Page 29

4.4.2 Mechanical positioning 4.4.2.1 Average seek time (including settling) Table 5: Mechanical positioning performance Command type Typical (ms) Max (ms) Read 8.2 9.2 Write 9.2 10.2 Read (Quiet Seek mode) 19.5 20.5 Write (Quiet Seek mode) 20.5 21.5 The terms "Typical" and "Max" are used throughout this document and are defined as follows: Typical The 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. The seek time is measured from the start of the actuator's motion to the start of a reliable read or write operation. A reliable read or write implies that error correction or recovery is not used to correct arrival problems. The average seek time is measured as the weighted average of all possible seek combinations. max Σ (m10 n)(Tnin + Tnout) n=1 Weighted Average (max + 1)(max) where max = Maximum seek length n = Seek length (1 to max) Tnin = Inward measured seek time for an n track seek Tnout = Outward measured seek time for an n track seek 4.4.2.2 Full stroke seek time (without command overhead, including settling) Table 6: Full stroke seek time Function Typical (ms) Max (ms) Read Write Read (Quiet Seek mode) Write (Quiet Seek mode) 14.7 17.7 15.7 18.7 32.5 35.5 33.5 36.5 Full stroke seek is measured as the average of 1,000 full stroke seeks with a random head switch from both directions (inward and outward). Deskstar 7K500 and Deskstar E7K500 Hard Disk Drive specification 15