Hitachi HUS151414VL3600, Specifications

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Hitachi Ultrastar 15K147 SCSI Hard Disk Drive Specification
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• Sustained disk-buffer transfer rate is the average rate measured while transferring multiple cylinders of data. It dif-
fers from the instantaneous transfer rate because of the time required to change tracks (Cylinder skew and Head
skew). In addition, time is added for the occasional missed transfer.
4.5.5 Buffering operation (read ahead/write cache)
This hard disk drive has a buffer for read ahead (see 20.8, “Segmented Caching” on page 244).
4.5.6 Throughput
4.5.6.1 Simple sequential access
Table 12: Simple sequential access performance (sector size 512 Byte case)
The above table gives the time required to read / write for a total of 32,768 consecutive blocks ( 16,777,216 bytes) accessed by
128 READ /WRITE commands. Typical and Max values are given by 100 % and 110% of T respectively, throughout the fol-
lowing performance description.
Note: It is assumed that a host system responds instantaneously.
T = A + B + C + 16,777,216/D
Where:
T = Calculated time
A = Command overhead (no cache hit)
B = Average seek time
C = Average latency
D = Sustained disk-buffer transfer rate
Operation Typical (ms) Maximum (ms)
Zone Model Read Write Read Write
Sequential Read / Write 0 147 GB 186 187 186 187
0 73 GB 185 185 186 185
0 36 GB 185 185 185 185
Sequential Read / Write 19 147 GB 251 251 251 251
19 73 GB 250 250 250 250
19 36 GB 249 250 249 250
Sequential Read / Write 23 147 GB 275 275 275 275
23 73 GB 274 275 274 275
23 36 GB -- -- -- --