Table of Contents
Advertisement
4.2.3
General performance characteristics
Sustainable disc transfer rate*:
Minimum
Maximum
Fibre Channel Interface maximum instantaneous transfer rate
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
Flaw reallocation performance impact (for flaws reallocated at format time
using the spare sectors per sparing zone reallocation scheme.)
*Assumes no errors and no relocated logical blocks. Rate measured from the start of the first logical block transfer to or
from the host.
4.3
Start/stop time
The drive accepts the commands listed in the Fibre Channel Interface Manual less than 3 seconds after DC
power has been applied.
If the drive receives a NOTIFY (ENABLE SPINUP) primitive through either port and has not received a START
STOP UNIT command with the START bit equal to 0, the drive becomes ready for normal operations within 30
seconds (excluding the error recovery procedure).
If the drive receives a START STOP UNIT command with the START bit equal to 0 before receiving a NOTIFY
(ENABLE SPINUP) primitive, the drive waits for a START STOP UNIT command with the START bit equal to 1.
After receiving a START STOP UNIT command with the START bit equal to 1, the drive waits for a NOTIFY
(ENABLE SPINUP) primitive. After receiving a NOTIFY (ENABLE SPINUP) primitive through either port, the
drive becomes ready for normal operations within 30 seconds (excluding the error recovery procedure).
If the drive receives a START STOP UNIT command with the START bit and IMMED bit equal to 1 and does
not receive a NOTIFY (ENABLE SPINUP) primitive within 5 seconds, the drive fails the START STOP UNIT
command.
The START STOP UNIT command may be used to command the drive to stop the spindle. Stop time is 30 sec-
onds (maximum) from removal of DC power.
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
the applicable bytes in page 08h. Prefetch and cache operations are independent features from the standpoint
that each is enabled and disabled independently using the Mode Select command; however, in actual opera-
tion, the prefetch feature overlaps cache operation somewhat as described in sections 4.5.1 and 4.5.2.
12
56 Mbytes/sec
116 Mbytes/sec
400 Mbytes/sec* per port
(dual port = 800 Mbytes/sec*)
Yes
Negligible
Barracuda ES.2 FC Product Manual, Rev. B
Advertisement
Table of Contents
