IBM DTLA-305040 - Deskstar 41.1 GB Hard Drive, Технические характеристики

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4.4.6 Throughput
4.4.6.1 Simple sequential access
1.00 1.26 0.95 1.20 Zone 14
0.50 0.60 0.48 0.57 Zone 0
DTLA-307XXX DTLA-305XXX DTLA-307XXX DTLA-305XXX
Max (sec) Typical (sec) Sequential
read
Figure 13. Simple Sequential Access performance
The above table gives the time required to read/write for a total of 8000x 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)
4.4.6.2 Random access
57 55 DTLA-307XXX
68 65 DTLA-305XXX
Maximum (sec) Typical (sec) Random read
Figure 14. Random Access Performance
The above table gives the time required to execute a total of 1000h read/write commands which access a
random LBA.
T = (A + B + C + 512/D + 512/E) * 4096 (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 40GV & 75GXP hard disk drive specifications
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