Seagate Barracuda ST11950N, Product Manual

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14 Barracuda 1 and 2 Product Manual, Rev. C
5.3 General performance characteristics
Minimum sector interleave 1 to 1
Data buffer to/from disc media 512-byte sector
Data transfer rate (
≤
1 sector)
Minimum 4.28 Mbytes/sec*
Maximum 7.06 Mbytes/sec*
Data transfer rate (< 1 track)
Minimum 3.56 Mbytes/sec*
Maximum 5.96 Mbytes/sec*
SCSI interface data
Asynchronous transfer rate * 5.0 Mbytes/sec** (non-wide)
(maximum instantaneous) 10.0 Mbytes/sec*** (wide)
Synchronous transfer rate fast and wide 0.5 to 10 Mbytes/sec
(ST11950N/ND and ST12550N/ND)
Synchronous transfer rate wide 5.0 to 20 Mbytes/sec
(ST11950W/WD and
ST12550W/WD)
Sector sizes
Default 512-byte data blocks
Variable in even-sector sizes 180 to 4,096 bytes
Read/write consecutive sectors on a track Yes
Flaw reallocation performance impact
Spare sectors per track reallocation
Negligible
Spare sectors per cylinder reallocation Negligible
Spare tracks per volume reallocation 35 msec (typical)
Overhead time for head switch 0.7 msec
Overhead time for one-track cylinder switch 1.6 msec (typical)
Average rotational latency 4.17 msec
* Rate measured from the start of the first sector transfer to or from the host.
** Assumes system ability to support 5.0 Mtransfers/sec and no cable loss.
*** Assumes system ability to support 5.0 Mtransfers/sec and no cable loss.
5.4 Start/stop time
Disabling the Motor Start option causes the motor to start as soon as power
is applied, causing the drive to become ready within 30 seconds after DC
power is applied at nominal voltage. If a recoverable error condition is
detected during the start sequence, the drive executes a recovery procedure
which may cause the drive to become ready in excess of 30 seconds. During
the start sequence the drive responds to some commands over the SCSI
interface. Stop time is less than 30 seconds (maximum) from removal of DC
power.
Enabling the Motor Start option causes the internal controller to accept the
commands listed in the
SCSI-2 Interface Product Manual (77738479) less
than 3 seconds after applying DC power. After receiving the Motor Start
command, the drive becomes ready for normal operation within 30 seconds