SSD Garbage Collection Timing and Parallel Write Handling
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In storage systems using solid state drives (SSDs), garbage collection processes can lead to delays in data write operations due to the need to wait for garbage collection to complete, resulting in increased response times when free space is low and unrequested data needs to be erased.
Innovation Solution
A storage control apparatus determines the timing for garbage collection based on data amount and response time thresholds, allowing it to execute garbage collection proactively and use a secondary memory area for data storage during collection, thereby reducing the impact on data write operations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If garbage collection is executed when free space is low, then free space is increased, but data write response time increases due to waiting for garbage collection to complete
Solution Approach 1:
The storage device is divided into multiple memory areas (first memory area and second memory area) to enable parallel operations. While garbage collection is executed on the first memory area, data writes can simultaneously occur in the second memory area, eliminating the waiting time and resolving the contradiction between maintaining free space and preserving write speed.
Solution Approach 2:
The storage control apparatus proactively determines to execute garbage collection based on the data amount of incoming write data before the free space becomes critically low. By initiating garbage collection in advance, the system prevents the situation where write operations must wait for garbage collection, thus maintaining both adequate free space and fast write response times.
2Loss of time
If garbage collection is executed proactively based on data amount, then data write response time is reduced, but control complexity increases
Solution Approach 1:
The storage control apparatus monitors the data amount of write operations and uses this feedback to dynamically determine when to execute garbage collection. This feedback mechanism enables proactive garbage collection decisions based on actual usage patterns, reducing response time while maintaining manageable control complexity through automated threshold-based decision making.
3Adaptability or versatility
If data is stored scatteredly with discontinuous logical addresses, then data storage flexibility is improved, but free space decreases due to fragmentation
Solution Approach 1:
By segmenting the storage device into multiple memory areas, the system can handle scattered data writes in different areas simultaneously. This segmentation prevents fragmentation from consuming all free space, as garbage collection can be performed on one area while other areas remain available for new writes, thus maintaining both storage flexibility and adequate free space.
Data Source
AI summary
A storage system includes a storage device including a first memory area and a second memory area, and a storage control apparatus configured to receive a first command requesting write of first data, cause the storage device to store the first data in the first memory area based on the first command, determine whether to cause the storage device to execute garbage collection on the first memory area based on a data amount of the first data, transmit a first instruction that instructs the storage device to execute the garbage collection on the first memory area, and cause the storage device to store second data in the second memory area when the garbage collection on the first memory area is being executed based on the first instruction and the processor receives a second command requesting write of the second data.