Interface Controller Wake Timing for HDD Power Savings
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing data storage devices face performance declines due to power-saving methods like DIPM and NCQ, which cause delays in data transfer and increased power consumption, especially during read seek operations in HDDs.
Innovation Solution
A storage device with an interface controller that can transition from an inactive to an active state before data is readable, using a processor to determine the optimal timing for waking up and starting data transfer, thereby reducing power consumption while maintaining performance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by stationary object
If the HDD wakes up from power saving state at the timing when data is readable from target sector, then power consumption is reduced, but data transfer start is delayed and performance declines
Solution Approach 1:
The interface controller wakes up from the inactive state in advance before the data is actually readable from the target sector. By performing the wake-up action preliminarily, the controller is ready to receive and process data immediately when it becomes available, eliminating the delay between data readiness and transfer start, thus resolving the contradiction between power saving and transfer speed
2Productivity
If the interface controller remains in active state to avoid wake-up delays, then data transfer performance is maintained, but power consumption increases
Solution Approach 1:
The interface controller dynamically transitions between active and inactive states based on the timing of data availability. Instead of remaining statically in the active state, the controller adapts its operational state, waking up in advance only when needed for data transfer, thus achieving both power efficiency and performance by making the system state dynamic rather than fixed
3Use of energy by stationary object
If power saving is executed during read seek operation, then power consumption is reduced, but wake-up time acts as overhead and delays data transfer
Solution Approach 1:
The wake-up action is performed in advance during the read seek operation, before the data becomes readable. This preliminary wake-up eliminates the wake-up time overhead from the critical data transfer path, as the controller is already active and ready when data arrives, thus resolving the time loss caused by power saving wake-up delays
Data Source
AI summary
A storage device for storing data includes: an interface controller connectable to a host via a interface, the interface controller having an active state capable of transmitting data to the host and an inactive state having a lower power consumption than the active state; a medium for storing data; a head for read out data stored in the medium; and a processor for executing a process including receiving a command for reading out data stored in the medium from the host, determining timing when the data read out from the medium reaches the interface controller, and starting transition of the interface controller from the inactive state into the active state before the determined timing.