Tape Drive Data Wrapping for Column Access Optimization
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Stream data recorded on tape media is not efficiently read out due to low random access performance, leading to prolonged read-out times when only some columns are accessed, as the tape medium's sequential access structure does not facilitate rapid column switching.
Innovation Solution
The system buffers and sorts stream data in a column order and time order, writing it onto the tape medium in a primary and secondary wrap format, with the primary data written in ascending order and secondary data in descending order, minimizing head movement during read-out.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Stability of the object's composition
If stream data is written to tape medium in chronological order, then the sequential access structure is maintained, but random access performance deteriorates and read-out time increases
Solution Approach 1:
The patent segments the tape medium into multiple wraps and further divides data into primary and secondary portions. Primary data is written in column order to the primary wrap, while secondary data is written in reverse column order to the secondary wrap. This segmentation allows the system to maintain sequential access structure while enabling faster access to specific columns by choosing the appropriate wrap based on access patterns.
Solution Approach 2:
The patent applies inversion by writing secondary data in reverse column order (from last column to first column) compared to the normal column order of primary data. This reverse ordering optimizes read-out performance for different access scenarios, allowing the system to quickly serve requests for different column ranges by selecting the wrap with the optimal data arrangement.
2Loss of information
If all columns are accessed sequentially, then complete data retrieval is achieved, but access time increases due to head movement across the tape
Solution Approach 1:
By dividing data into primary and secondary portions across different wraps with different column orderings, the system can retrieve complete data faster. When all columns are needed, the system can efficiently read from both wraps in parallel or sequence rather than scanning the entire tape in a single sequential pass, reducing total access time while maintaining data completeness.
Solution Approach 2:
The data is pre-organized into primary and secondary wraps with optimized column orderings before access occurs. This preliminary arrangement allows the system to quickly serve different access scenarios without performing real-time reordering, reducing access time while ensuring complete data retrieval when needed.
3Productivity
If data is buffered and sorted before writing, then read-out efficiency is improved, but device complexity increases
Solution Approach 1:
The system performs buffering and sorting of stream data into primary and secondary portions with specific column orderings before writing to the tape medium. This preliminary processing, while adding complexity to the writing phase, significantly improves read-out efficiency by eliminating the need for complex reordering operations during data access, thereby enhancing overall productivity.
Solution Approach 2:
The patent changes the organizational parameters of the stored data by using different column orderings (normal order for primary, reverse order for secondary) in different wraps. This parameter change enables more efficient data retrieval for various access patterns, improving read-out efficiency despite the increased complexity of the initial data processing and organization.
Data Source
AI summary
An information processing device includes: a memory; and a processor coupled to the memory, the processor being configured to: sort stream data buffered in units of wraps of a sequential recording medium, in a column order and a time order of the stream data, as primary data to be written into a primary wrap of the sequential recording medium; and control writing of the sorted primary data into the primary wrap, wherein the sorting of the stream data is configured to sort secondary data to be written into a secondary wrap that follows the primary wrap, in a reverse order of the column order and in the time order, and wherein the controlling of the primary data is configured to control writing of the sorted secondary data into the secondary wrap.