Dynamic NAND Status Timing Adjustments with Closed Loop Feedback
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current storage devices face inefficiencies in bus traffic due to inaccurate status polling times, which can lead to unnecessary traffic or reduced performance, as they fail to account for temperature variations and back pressure, relying on static delay times that do not adapt to dynamic conditions.
Innovation Solution
Implement a closed-loop, dynamic adjustment mechanism using a controller to adjust status polling delay times based on a running average of polling commands, employing a circular buffer and PID controller to optimize bus utilization by accurately detecting when operations are complete.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If the controller uses static delay times for status polling, then the device complexity is reduced, but the bus traffic efficiency deteriorates due to inaccurate polling timing that does not account for temperature variations and back pressure
Solution Approach 1:
The patent implements dynamic delay time adjustment where the controller modifies the status polling delay based on real-time conditions including temperature variations and back pressure. The controller adjusts the delay time dynamically rather than using fixed static values, allowing optimization of bus traffic efficiency under varying operational conditions while maintaining manageable complexity through structured adjustment logic
Solution Approach 2:
The controller incorporates feedback mechanisms to monitor actual polling results and adjust delay times accordingly. By observing whether status polls complete successfully or need retransmission, the controller modifies future polling delays to optimize bus utilization, creating a closed-loop system that continuously improves traffic efficiency based on actual performance data
2Reliability
If the controller starts status command polls earlier to account for back pressure, then the reliability of command completion detection is improved, but the bus traffic increases due to unnecessary early polling
Solution Approach 1:
The controller dynamically adjusts polling timing based on real-time assessment of back pressure conditions and temperature variations. Rather than using fixed early polling schedules, the system adapts the polling start time and interval dynamically, reducing unnecessary bus traffic during low-back-pressure periods while ensuring reliable detection when needed
Solution Approach 2:
The system changes the timing parameters of status polling based on operational conditions. The controller modifies delay times and polling intervals as parameters adapt to current system state, optimizing the balance between detection reliability and traffic reduction by adjusting these parameters rather than using static values
3Ease of operation
If the controller uses fixed delay times for all commands, then the ease of operation is improved, but the productivity decreases due to inability to adapt to different command types and conditions
Solution Approach 1:
The controller implements dynamic delay adjustment that adapts to different command types (program, erase, read) and operational conditions. Each command type receives appropriate delay timing, and the system further optimizes based on real-time temperature and back pressure conditions, achieving high productivity while maintaining ease of operation through automated adaptation
Solution Approach 2:
The system changes delay time parameters automatically based on command type and environmental conditions. Rather than requiring manual configuration for different scenarios, the controller adjusts parameters autonomously, maintaining ease of operation while significantly improving productivity through adaptive timing for each specific command and condition
Data Source
AI summary
A storage device may dynamically adjust a delay time associated with status polling of a memory device. The storage device includes a memory device to store data and to operate on the data based on commands received from the storage device. A controller on the storage device sends a command to the memory device for the memory device to operate on the data based on the command and sends a poll to the memory device to determine when the memory device has completed processing the command. The controller may record a status poll count for the command in a buffer and compute a running average value for status poll counts in the buffer. The controller compares the running average value with a target window and adjusts a delay time between sending another command and another poll based on based on the comparison.