The Scsi Parameter/Initialize; Synchronous Transfer; Data Transfer Rates - Intel SRCU31A - Server RAID U3-1A Controller User Manual

The SCSI Parameter/Initialize

The SCSI parameters configure a physical drive (especially its performance). By changing the
SCSI parameters, you can:
•
Set the Synchronous Transfer Rate (terms_sync_transfer)
•
Change the Settings of the Hard Disk Drive Cache (terms_cache_settings)
•
Enable or Disable the Disconnect Feature (terms_disconnect)
•
Enable or Disable the Tagged Queues (terms_tagged_queues)
WARNING
By changing these parameters on a new hard disk or a hard disk which has been connected to a
non-compatible RAID controller, the hard disk will be initialized (terms_initialization) and all
data on this hard disk will be lost.
You can access the change SCSI Parameters / Initialize menu by clicking the right mouse button on
a physical drive in the Physical Drives Windows (
Configuration).

Synchronous Transfer

Different to the older asynchronous transfer mode, synchronous transfer offers higher transfer rates
on the SCSI bus. The maximum synchronous data transfer rate depends on the width of the SCSI
bus (8 bit narrow SCSI, 16 bit wide SCSI) and the frequency of the signals on the SCSI bus
(10 MHz for Fast SCSI, 20 MHz for Ultra SCSI and 40 MHz for Ultra2 SCSI and Ultra160 SCSI).
The maximum data transfer rates are shown in Table 23.
Table 23.

Data Transfer Rates

Fast SCSI
Ultra SCSI
Ultra2 SCSI
Ultra160
* (LVD SCSI (low voltage differential) only)
✏
NOTE
The maximum synchronous data transfer rate between a SCSI device and the Intel RAID Controller
SRCU31 can be limited. This limitation may become necessary if a particular SCSI cabling does
not allow the maximum rate the controller and the drive could achieve. Adjust the synchronous
transfer rate in the SCSI parameters / Initialize menu (pdisk_parameters).
Storage Console Plus
view_physical_conf)
Narrow SCSI
(8 Bit)
10 MB/s
20 MB/s
-
-
(View > Physical
Wide SCSI
(16 Bit)
20 MB/s
40 MB/s
80 MB/s*
160 MB/s*
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