IBM TS4500, Введение и руководство по планированию

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Table 28 shows the typical time required for the TS4500 tape library to inventory
all tiers during a bulk load.
Table 28. Typical time required for the TS4500 tape library to inventory all tiers
Frame Component
Typical Time to Inventory all Tiers in
Seconds
Full HD slot 15
Model L25/D25 column of full HD slots 280
Model S24/S25 column of full HD slots 415
Model L55/D55 column of full HD slots 390
Model S54/S55 column of full HD slots 580
Mount performance
Mounts per hour is a measure of the overall capability of the cartridge accessor
and tape drives. It is defined as the number of cartridges that the TS4500 tape
library can mount in one hour.
A mount, often called the demount and mount cycle, involves the following steps:
(1) removing the cartridge from a drive; (2) returning it to a storage slot; (3)
collecting another cartridge from a random storage slot; (4) moving it to the drive;
and (5) loading the cartridge into the drive. Table 29 shows the mount performance
for a TS4500 tape library with all mounts coming from Tier 0, which are the
single-deep slots on the door side of the HD frame.
Table 29. Mount performance for a TS4500 tape library with all mounts coming from Tier 0.
Library Configuration
Maximum Mounts Per Hour
Single Accessor Dual Accessor
1 frame 490 N/A
2 frames 460 N/A
4 frames 360 730
6 frames 315 720
8 frames 270 680
12 frames 220 620
18 frames 180 550
Specifications were produced from models, but are consistent with test results. The dual accessor data assumes that
each cartridge is mounted in a drive that is located within the same library zone.
Chapter 1. Overview
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