IBM System Storage TS3500, Introduction And Planning Manual

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Table 26. Mount performance for drives in a TS3500 Tape Library with dual accessors but without HD
frames (continued)
Library Configuration
(Active Frames
1
)
Mounts Per Hour
2
Notes:
1. Active frames are all frames in a dual-accessor library except service bay frames.
2. Specifications were produced from models, but are consistent with test results. This data assumes that the library
is partitioned into at least two logical libraries, such that each of the cartridges located in the two zones are
mounted in drives within each zone with no accessor path overlap. Detailed performance data and tips about
maximizing the performance of a TS3500 Tape Library are available in the
IBM TotalStorage 3584 Tape Library
Performance white paper. For information about this document, contact your IBM Representative.
In order to understand how HD frames affect mount performance and cartridge
move time, refer to “HD frame performance considerations” on page 87.
Import and export performance with virtual I/O slots
This topic describes import and export performance in the TS3500 Tape Library
with virtual I/O slots enabled.
Virtual I/O slots increase the quantity of available I/O slots by allowing storage
slots to appear to the host as I/O slots. With virtual I/O slots, the library
automatically moves cartridges between the I/O stations and the storage slots. In
this way, the library enhances its import and export capabilities.
Imports per hour and average I/O station drain time can vary depending on
whether a library has single or dual accessors, and whether the library has HD
frames.
Imports per hour is defined as the average number of cartridges imported in
one hour. Average I/O station drain time is defined as the time it takes one active
accessor to import 16 cartridges from one I/O station into the library. Both
specifications assume there is no other activity in the library.
Table 27 shows the imports per hour and average I/O station drain time using one
active accessor in a TS3500 Tape Library with virtual I/O slots enabled, but
without HD frames. Table 28 on page 87 shows imports per hour in a TS3500 Tape
Library with dual active accessors and virtual I/O slots enabled, but without HD
frames.
Table 27. Specifications for imports per hour and average I/O station drain time for a TS3500 Tape Library using one
active accessor
Library configuration
I/O station in frame 1 I/O station in center frame
Imports per hour
1
Average I/O Station
Drain Time (in
Seconds)
1
Imports per hour
1
Average I/O Station
Drain Time (in
Seconds)
1
1 frame 829 69 N/A N/A
2 frames 725 79 N/A N/A
4 frames 640 90 678 85
6 frames 585 98 639 90
8 frames 536 107 603 95
12 frames 466 123 556 103
16 frames 412 139 513 112
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IBM System Storage TS3500 Tape Library with ALMS: Introduction and Planning Guide