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Cheetah 15K.5 FC Product Manual, Rev. F
4.2.2 Format command execution time (minutes)
4.2.3 General performance characteristics
4.3 Start/stop time
If the Motor Start option is disabled, the drive becomes ready within 20 seconds after DC power is applied. If a
recoverable error condition is detected during the start seq uence, the dr ive execu t es a re cover y proce dure and
the time to become ready may exceed 20 seconds. During spin up to ready time, the drive responds to some
commands over the FC interface in less than 3 seconds after application of power. Stop time is 30 seconds
(maximum) from removal of DC power.
If the Motor Start option is enabled, the internal controller accepts the commands listed in the Fibre Channel
Interface Manual less than 3 seconds after DC power has been applied. After the Motor Start command has
been received, the drive becomes ready for normal operations within 20 seconds (excluding the error recovery
procedure). The Motor Start command can also be used to command the drive to stop the spindle.
There is no power control switch on the drive.
4.4 Prefetch/multi-s eg m en te d cache control
The drive provides a prefetch (read look-ahead) and multi-segmented cache control algorithms that in many
cases can enhance system performance. Cache refers to the drive buffer storage space when it is used in
cache operations. To select this feature, the host sends the Mode Select command with the proper values in
ST3300655FC ST3146855FC ST373455FC
Maximum (with verify) 120 90 60
Maximum (without verify) 60 45 30
Sustainable disc transfer rate*:
Minimum 73 Mbytes/sec
Maximum 125 Mbytes/sec
Fibre Channel Interface maximum instantaneous transfer rate 800 Mbytes/sec* per port
(dual port = 1600 Mbytes/sec*)
Logical block sizes
Default is 512-byte data blocks
Sector sizes variable to 512, 520, 524 and 528 bytes.
Read/write consecutive sectors on a track Yes
Flaw reallocation performance impact (for flaws reallocated at format time
using the spare sectors per sparing zone reallocation scheme.) Negligible
Average rotational latency 2.0 msec
*Assumes no errors and no relocated logical blocks. Rate measured from the start of the first logical block transfer to or
from the host.