IBM IC35L020 - Deskstar 20 GB Hard Drive - Figure 13. Random Access Performance

T = A + B + C + (16,777,216/D) + (512/E) (READ)
where
T = Calculated time (in seconds)
A = Command process time (Command Overhead) (in seconds)
B = Average seek time (in seconds)
C = Average latency (in seconds)
D = Sustained disk-buffer transfer rate (bytes/s)
E = Buffer-host transfer rate (bytes/s)
4.3.6.2 Random access
The following figure illustrates the case of 3-disk Disk Enclosure.
6055Random Read
Maximum (s)Typical (s)Operation
Figure 13. 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 (in seconds)
A = Command process time (Command Overhead) (in seconds)
B = Average seek time (in seconds)
C = Latency
D = Average sustained disk-buffer transfer rate (bytes/sec)
E = Buffer-host transfer rate (bytes/sec)
Deskstar 60 GXP Hard disk drive specification
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