Tape Storage Reading Order Optimization
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current tape storage systems do not optimize reading orders to minimize reading time effectively, as they fail to consider changes in tape running direction, leading to reduced reading speed and efficiency.
Innovation Solution
An information processing apparatus and method that calculates an integrated speed for each reading order based on the distance and tape running speed between objects across multiple wraps, selecting an order that maximizes integrated speed by considering the running direction changes.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Length of moving object
If the reading order is optimized based on distance only, then the reading path is shortened, but the tape running direction changes increase causing reduced reading speed
Solution Approach 1:
The patent changes the optimization parameters from distance-only to a composite metric that includes both distance and direction change penalties. The reading order is selected based on minimizing the sum of travel distance and direction change costs, where direction changes between wraps are penalized. This parameter change resolves the contradiction by preventing excessive direction changes that would slow down tape reading.
Solution Approach 2:
The patent introduces dynamic consideration of tape running direction in the reading order optimization. Instead of static distance-based ordering, the system dynamically evaluates reading sequences based on current tape direction and predicts future direction changes. This dynamic approach allows the system to maintain higher tape speeds by reducing unnecessary direction reversals while still achieving efficient data retrieval.
2Adaptability or versatility
If the tape running direction changes frequently to access objects in different wraps, then the access flexibility is improved, but the reading speed decreases
Solution Approach 1:
The patent modifies the optimization criterion to include a direction change penalty parameter. When selecting reading order, the system calculates a composite score that combines distance metrics with direction change costs. By adjusting the weight of direction change penalties, the system can balance between access flexibility and reading speed, resolving the contradiction by preventing excessive direction changes while maintaining reasonable access capability.
3Device complexity
If the reading order follows the application request sequence, then the system complexity is low, but the reading efficiency is reduced
Solution Approach 1:
The patent implements preliminary optimization of reading order before actual data retrieval. The scheduler pre-calculates the optimal reading sequence by evaluating distance and direction change factors for all requested objects. This preliminary action allows the system to maintain relatively simple operational logic during execution while achieving high reading efficiency through advance planning of the reading sequence.
Data Source
AI summary
An information processing apparatus includes a memory, and a processor coupled to the memory and the processor configured to obtain requests for reading objects that exist in a plurality of wraps in different running directions on a tape of a tape storage, calculate an integrated speed for each of a plurality of orders of reading the objects based on a distance between the objects and a running speed of the tape between the objects, and select, from among the plurality of orders, an order that maximizes the integrated speed.