Cache Controller Dynamic Area Allocation for Power Capacity
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing disk array apparatuses face issues with data loss during power failures due to the fixed threshold for dirty data protection, leading to prolonged data processing times when the backup power supply capacity falls below a certain level, causing a shift from write-back to write-through state.
Innovation Solution
A method to dynamically allocate a permitted and inhibited area in the cache memory based on the power supply capacity of the backup power supply, allowing for flexible storage of dirty data and read data to prevent data loss and reduce processing time by adjusting the write operation state accordingly.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If a fixed threshold for dirty data protection is used, then data protection is simplified, but data processing time increases when backup power supply capacity falls below the threshold
Solution Approach 1:
The patent applies dynamics by transitioning from a fixed threshold to a dynamic threshold that adapts to the actual backup power supply capacity. The control unit continuously monitors battery capacity and adjusts the dirty data threshold accordingly, allowing the system to operate in write-back mode whenever possible rather than forcing a shift to write-through mode when capacity drops below a fixed threshold.
Solution Approach 2:
The patent changes the parameter of the dirty data protection threshold from a fixed value to a variable value that depends on backup power supply capacity. This allows the threshold to be optimized in real-time based on available power, preventing unnecessary mode switches and maintaining efficient data processing performance.
2Reliability
If the disk array apparatus shifts from write-back state to write-through state when backup power capacity falls below threshold, then dirty data protection is ensured, but data processing time becomes long
Solution Approach 1:
The system dynamically adjusts the dirty data threshold based on real-time backup power capacity monitoring. This prevents unnecessary transitions to write-through mode, allowing the system to maintain write-back operation and high data processing speed even when battery capacity decreases, while still ensuring data protection through adaptive threshold management.
Solution Approach 2:
The control unit implements feedback by continuously monitoring the backup power supply capacity and using this information to adjust the dirty data protection threshold. This closed-loop control ensures that the system maintains optimal performance while adapting to changing power availability, avoiding premature shifts to slower write-through operation.
3Device complexity
If a fixed threshold is used for dirty data protection, then control is simplified, but the system cannot adapt to battery capacity deterioration over time
Solution Approach 1:
The patent implements a dynamic control mechanism that automatically adapts to battery capacity deterioration. The control unit monitors power supply capacity over time and adjusts the dirty data threshold accordingly, allowing the system to maintain optimal performance throughout the battery's lifecycle without manual intervention or complex reconfiguration.
Solution Approach 2:
The system performs self-adjustment by automatically monitoring its own power supply capacity and modifying its operational parameters (dirty data threshold) accordingly. This self-service capability eliminates the need for external configuration or manual adaptation when battery capacity changes, maintaining both simplicity and adaptability.
Data Source
AI summary
According to an aspect of the embodiment, a cache controller sets, when power supply capacity information is acquired at an update period, a size of a permitted area in which the writing of dirty data is permitted and a size of an inhibited area in which the writing of the dirty data is inhibited in a cache memory, according to the power supply capacity information. The cache controller stores the dirty data or read data read out from a disk array in the permitted area, or stores only the read data in the inhibited area.