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2 format command execution time (minutes), 3 general performance characteristics, 3 start/stop time – Seagate Cheetah 15K.5 FC ST373455FC User Manual

Page 22: 4 prefetch/multi-segmented cache control

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Cheetah 15K.5 FC Product Manual, Rev. D

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 sequence, the drive executes a recovery procedure 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-segmented 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.

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