Datasheet

Travelstar 80GN Hard Disk Drive Specification

4.4 Performance characteristics

Drive performance is characterized by the following parameters:

• Command overhead

• Mechanical head positioning

- Seek time

- Latency

• Data transfer speed

• Buffering operation (read ahead/write cache)

Note: All the above parameters contribute to drive performance. There are other parameters that contribute to the

performance of the actual system. This specification tries to define the bare drive characteristics, not system

throughput, which depends on the system and the application.

The following table gives a typical value for each parameter. The detailed descriptions are found in Section 5.0,

“Data integrity” beginning on page 21.

4.4.1 Command overhead

Command overhead time is defined as the interval from the time that a drive receives a command to the time that

the actuator starts its motion

4.4.2 Mechanical positioning

4.4.2.1 Average seek time (including settling)

Table 4: Performance characteristics

Function

Average random seek time - read (ms) 12

Average random seek time - write (ms) 14

Rotational speed (RPM) 4200

Power-on-to-ready (sec) 3.0

Command overhead (ms) 1.0

Disk-buffer data transfer (Mb/s) 350

Buffer-host data transfer (Mb/s) 100

Table 5: Mechanical positioning performance

Command type Typical (ms) Max (ms)

Write 14 17