Hitachi Deskstar 7K80, Specifications

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Deskstar 7K80 Hard Disk Drive Specification
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4.5.5 Throughput
4.5.5.1 Simple sequential access
The following table illustrates simple sequential access for the enclosure.
The above table gives the time required to read a total of 8000h consecutive blocks (16,777,216 bytes) accessed by
128 read commands. Typical and Max values are given by 105% and 110% of T respectively throughout following
performance description.
T = A + B + C + 16,777,216/D + 512/E (READ)
where
T = Calculated time (sec)
A = Command process time (Command overhead) (sec)
B = Average seek time (sec)
C = Average latency (sec)
D = Sustained disk-buffer transfer rate (byte/sec)
E = Buffer-host transfer rate (byte/sec)
Note: It is assumed that a host system responds instantaneously and host data transfer is faster than sustained data
rate.
4.5.5.2 Random access
The following table illustrates simple sequential access for enclosure.
The above table gives the time required to execute a total of 1000h read commands which access a single random
LBA. Typical and Max values are given by 105% and 110% of T respectively throughout following performance
description.
T = 4096(A + B + C+ 512/D + 512/E) (READ)
where
T = Calculated time (sec)
A = Command process time (Command overhead) (sec)
B = Average seek time (sec)
C = Latency
Table 13: Simple Sequential Access performance
Operation Typical (sec) Max (sec)
Sequential Read (Zone 0) 0.3 0.32
Sequential Read (Zone 29) 0.61 0.63
Table 14: Random Access Performance
Operation Typical (sec) Max (sec)
Random Read 55.9 58.6