IBM IC35L040AVVN07-0 - 40GB IDE Deskstar 120GXP 7200RPM UATA-100..., Технические характеристики

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4.4.5 Throughput
4.4.5.1 Simple sequential access
The following figure illustrates the case of the three-disk enclosure.
0.81 0.77 Sequential Read (Zone 30)
0.40 0.38 Sequential Read (Zone 0)
Max (sec) Typical (sec) Operation
Figure 13. Simple Sequential Access performance
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.
Note: It is assumed that a host system responds instantaneously and host data transfer is faster than
sustained data rate.
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)
4.4.5.2 Random access
The following figure illustrates the case of the three-disk enclosure.
58 55 Random Read
Max (sec) Typical (sec) Operation
Figure 14. Random Access Performance
The above table gives the time required to execute a total of 1000h read commands which access a single
random LBA.
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
D = Average sustained disk-buffer transfer rate (byte/sec)
E = Buffer-host transfer rate (byte/sec)
Deskstar 120GXP hard disk drive specifications
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