Memory Pre-Read Buffer Flags for Low-Latency Sequential Reads
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Memory systems experience delays and inefficiencies due to the use of command queues with a depth of one, leading to idle windows and increased latency during sequential read operations, particularly when polling buffer status for data readiness.
Innovation Solution
Implementing a pre-read algorithm that automatically monitors the readiness of data in a buffer by setting flags for pre-read data, allowing direct transfer without polling, thus reducing latency and improving data transfer efficiency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If a command queue with depth of one is used, then device complexity is reduced, but data transfer latency increases and idle windows are created during sequential read operations
Solution Approach 1:
The system performs pre-read operations during idle windows to fetch data in advance before it is actually needed. The memory system predicts upcoming read requests and proactively retrieves the data from storage, placing it in a buffer ready for immediate transfer. This preliminary action eliminates the idle window and reduces latency by having data ready when the host system needs it.
2Reliability
If polling buffer status is performed to check data readiness, then data transfer reliability is improved, but processing time increases and efficiency decreases
Solution Approach 1:
Instead of active polling, the system uses an interrupt-based feedback mechanism. When data is successfully transferred to the buffer during pre-read operations, the memory system sets a flag or generates an interrupt signal to notify the host system. This passive feedback approach maintains reliability by ensuring data is ready before transfer, while eliminating the continuous polling cycle that reduces efficiency.
3Loss of time
If pre-read operations are performed during idle windows, then data transfer latency is reduced, but device complexity increases due to additional monitoring and flag management
Solution Approach 1:
The buffer is divided into multiple segments or portions that can independently store pre-read data. Each segment can be managed separately with its own readiness flags, allowing the system to handle multiple data streams concurrently. This segmentation simplifies the monitoring logic by breaking down the complex task of tracking buffer status into smaller, manageable units, reducing the overall complexity of flag management while maintaining low latency performance.
Data Source
AI summary
Methods, systems, and devices for a pre-read algorithm for a sequential read operation of a memory system are described. In response to executing a first command indicating to read a first set of data, the memory system may store a second set of data in a buffer. The buffer may include multiple portions and a subset of the second set of data may be stored in a first portion of the multiple portions. Further, the memory system may set a value of a flag associated with the first portion to indicate that the subset of the second set of data has been transferred to the first portion. Moreover, the memory system may receive a third command to read the subset of the second set of data and transmit the subset of the second set of data based on the third command and the value of the flag.