Fujitsu MAW3073NC, Руководство по эксплуатации/техническому обслуживанию

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C141-E226 1-3
(5) High speed data transfer
Such a high data transfer rate on the SCSI bus can be useful with the large capacity buffer in the
HDD.
•
8-bit SCSI: The data transfer rate on the SCSI bus is 40 MB/s maximum at the
synchronous mode.
•
16-bit SCSI: The data transfer rate on the SCSI bus is 320 MB/s maximum at the paced
transfer synchronous mode.
Note:
The maximum data transfer rate in asynchronous mode may be limited by the response time of
initiator and the length of SCSI bus length. The maximum data transfer rate in synchronous
mode may be limited by the cable length, transmission characteristics of the SCSI bus and the
connected SCSI device number.
(6)
Continuous block processing
The addressing method of data blocks is logical block address. The initiator can access data by
specifying block number in a logically continuous data space without concerning the physical
structure of the track or cylinder boundaries.
The continuous processing up to [64K-1] blocks in a command can be achieved, and the HDD can
perform continuous read/write operation when processing data blocks on several tracks or cylinder.
(7)
Multi-segment data buffer
The data buffer is 8M bytes. Data is transferred between SCSI bus and disk media through this
data buffer. This feature provides the suitable usage environment for users.
Since the initiator can control the disconnect/reconnect timing on the SCSI bus by specifying the
condition of stored data to the data buffer or empty condition of the data buffer, the initiator can
perform the effective input/output operations with utilizing high data transfer capability of the
SCSI bus regardless of actual data transfer rate of the disk drive.
(8) Cache
feature
After executing the READ command, the HDD reads automatically and stores (prefaces) the
subsequent data blocks into the data buffer (Read-ahead caching).
The high speed sequential data access can be achieved by transferring the data from the data buffer
without reassessing the disk in case the subsequent command requests the perfected data blocks.
The write cache feature is supported. When this feature is enabled, the status report is issued without
waiting for completion of write processing to disk media, thereby enabling high speed write processing.