IBM Ultrium Gen 6, Installation And User Manual

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The drive reads tapes that have been written by other licensed Ultrium 6 drives,
and writes to tapes that can be read by other licensed Ultrium 6 drives.
In addition to using the IBM LTO Ultrium Data Cartridge with up to 2500 GB
capacity, the drive also offers read/write capability for certified LTO Ultrium tape
cartridges.
Important: The IBM Half High LTO Ultrium 6 Tape Drive cartridge has a limited
one year warranty provided by IBM Storage Media. If any defect in material or
manufacture appears within one year of the date of original purchase of this
product, it will be replaced or the purchase price refunded. Please contact the seller
of the of IBM Data Storage products or visit us on the web at http://www-
03.ibm.com/systems/storage/media/. Within the US and Canada, call toll free
(888)426-6334 or (888)IBM-MEDIA) to receive warranty service or product
information.
Speed matching
To improve system performance, the drive uses a technique called speed matching to
dynamically adjust its native (uncompressed) data rate to the slower data rate of a
server.
With speed matching, the drive operates at different speeds when reading or
writing the Ultrium 5 or Ultrium 6 cartridge format. Native data rates are as
follows in the table below.
Table 4. Performance parameters
Ultrium generation media
Generation 6 media Generation 5 media Generation 4 media
Speed matching data
rates (MB/second) 160.0 140.0 120.0
150.77 130.0 113.1
141.54 120.0 106.0
132.31 112.7 99.2
123.08 105.5 92.3
113.85 98.2 85.3
104.62 90.9 78.5
95.38 83.6 71.4
86.15 76.4 64.6
76.92 69.1 57.6
67.69 61.8 50.7
58.46 53.5 43.8
49.23 46.3 36.9
40.00 40.0 30.5
If the server net (compressed) data rate is between two of the preceding native
data rates, the drive calculates the appropriate data rate at which to operate. Speed
matching dramatically reduces backhitch, the condition that occurs when a tape
stops, reverses, and restarts motion. A backhitch is usually the result of a mismatch
between the data rates of the server and the drive.
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IBM Half High LTO Ultrium Gen 6 Internal SAS Tape Drive: Installation and User's Guide