IBM TotalStorage Ultrium 3580 L23, Руководство по настройке и эксплуатации

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Table 1. 3580 Tape Drive Models
Model SCSI Attachment Ultrium 1 or Ultrium 2
L11 LVD Ultrium 1
L13 LVD Ultrium 1
L23 LVD Ultrium 2
H11 HVD Ultrium 1
H13 HVD Ultrium 1
H23 HVD Ultrium 2
Drive Performance
If you run applications that are highly dependent on tape-processing speed, you
can take advantage of the significant performance improvements provided by the
IBM 3580 Ultrium 2 Tape Drive. Table 2 lists the performance characteristics of
both the Ultrium 2 and Ultrium 1 models.
Table 2. Performance characteristics of the Ultrium 2 Tape Drive and the Ultrium 1 Tape Drive
Performance Characteristic
Tape Drive
Ultrium 2 Tape Drive Ultrium 1 Tape Drive
Native sustained data rate 35 MB/s
(with Ultrium 2 media)
15 MB/s
20 MB/s
(with Ultrium 1 media)
Compressed data rate (at 2:1
compression) 70 MB/s
(with Ultrium 2 media)
30 MB/s
40 MB/s
(with Ultrium 1 media)
Maximum sustained data rate (at
maximum compression) 107 MB/s (Ultra160) 60 MB/s
Burst data rate for Low Voltage
Differential (LVD) SCSI drives 160 MB/s (Ultra160) 80 MB/s (Ultra2)
Burst data rate for High Voltage
Differential (HVD) SCSI drives 40 MB/s (Ultra) 40 MB/s (Ultra)
Nominal load-to-ready time 15 seconds 20 seconds
Nominal unload time 15 seconds 18 seconds
Average search time to first byte of
data 49 seconds 73 seconds
Note: All sustained data rates are dependent on the capabilities of the interconnect (for example, an UltraSCSI bus
is limited to less than 40MB/sec).
By using the built-in data-compression capability of the tape drives, you can
achieve greater data rates than the native data transfer rate. However, the actual
throughput is a function of many components, such as the host system processor,
disk data rate, block size, data compression ratio, SCSI bus capabilities, and system
or application software.
2
IBM 3580 Ultrium Tape Drive Setup and Operator Guide