Hitachi HTS541040G9AT00 Specifications - Page 28

Performance characteristics - read speed

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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 defines the essential characteristics of the drive. It does not include system throughput which is dependent 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 19. Table 5: Performance characteristics Function Average random seek time - read (ms) Average random seek time - write (ms) Rotational speed (RPM) Power-on-to-ready (sec) Command overhead (ms) Disk-buffer data transfer (Mb/s) Buffer-host data transfer (Mb/s) 12 14 5400 3.5 1.0 493 max 100 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 6: Mechanical positioning performance Command type Typical (ms) Max (ms) Read 12 14 Write 13 15 Travelstar 5K100 Hard Disk Drive Specification 14

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Travelstar 5K100 Hard Disk Drive Specification
14
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 defines the essential characteristics of the drive.
It does not
include system throughput which is dependent 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 19.
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 5: Performance characteristics
Function
Average random seek time - read (ms)
12
Average random seek time - write (ms)
14
Rotational speed (RPM)
5400
Power-on-to-ready (sec)
3.5
Command overhead (ms)
1.0
Disk-buffer data transfer (Mb/s)
493 max
Buffer-host data transfer (Mb/s)
100
Table 6: Mechanical positioning performance
Command type
Typical (ms)
Max (ms)
Read
12
14
Write
13
15