Seagate ES.2 FC, ST31000640FC manual Start/stop time, Prefetch/multi-segmented cache control, 4.2.3

Models: ST31000640FC ES.2 FC

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4.2.3

4.2.3

General performance characteristics

 

Sustainable disc transfer rate*:

 

Minimum

56 Mbytes/sec

Maximum

116 Mbytes/sec

Fibre Channel Interface maximum instantaneous transfer rate

400 Mbytes/sec* per port

 

 

(dual port = 800 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

Negligible

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.

4.3Start/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.

4.4Prefetch/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.

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Barracuda ES.2 FC Product Manual, Rev. B

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Seagate ES.2 FC manual Start/stop time, Prefetch/multi-segmented cache control, 4.2.3, General performance characteristics