SSD Controller Sideband Information Aggregation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing methods for sending sideband information over PCIe interfaces in SSDs lead to inefficiencies in power consumption due to unnecessary link state switches, as sideband information is sent even when the link is in an inactive state, causing the system to wake up and consume more power.
Innovation Solution
A data storage device with a controller that creates thresholds for sending sideband information based on link states, retaining the information until the thresholds are reached, and sending it in a first-in first-out order to minimize power consumption by avoiding frequent link state switches.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If sideband information is sent continuously over the PCIe interface, then communication reliability is improved, but power consumption increases due to frequent link state switches
Solution Approach 1:
The system performs preliminary actions by accumulating sideband information in a buffer before sending it to the host device. The controller continuously stores incoming sideband information in an internal buffer, and only sends the accumulated data when the link is in an active state, avoiding frequent wake-ups and link state switches.
Solution Approach 2:
The invention maintains continuity of useful action by keeping the link in a persistent active state once awakened, allowing batch transmission of accumulated sideband information. This eliminates the need to repeatedly wake and sleep the link, reducing the frequency of state transitions and associated power consumption.
2Use of energy by moving object
If the link is kept in an inactive state for power saving, then power consumption is reduced, but link state switches increase when sideband information needs to be sent
Solution Approach 1:
The controller performs preliminary action by accumulating sideband information in a buffer while the link remains inactive. This preparation allows the system to send multiple pieces of sideband information in a single wake-up event, reducing the frequency of link state switches and simplifying power management.
Solution Approach 2:
The internal buffer acts as an intermediary between the inactive link state and the need to transmit sideband information. It decouples the transmission timing from the link state, allowing the system to remain inactive while accumulating data, then transmit in batches when awakened, reducing the complexity of continuous link state management.
3Use of energy by moving object
If sideband information is aggregated and sent in batches, then power consumption is reduced by minimizing wake-ups, but transmission time is increased
Solution Approach 1:
The system performs preliminary accumulation of sideband information in the buffer, which allows for batch transmission. Although individual transmissions are delayed until thresholds are met, the overall transmission process is optimized by consolidating multiple small transmissions into fewer, larger transmissions that occur when the link is already active.
Solution Approach 2:
Once the link is awakened, the system maintains continuous transmission of accumulated sideband information until the buffer is empty. This continuous action during the active state minimizes the total time the link spends in transition states, optimizing the trade-off between power consumption and transmission time.
Data Source
AI summary
A data storage device includes a memory device and a controller coupled to the memory device. The controller is configured to create one or more thresholds for sending sideband information to a host device, determine that a link state is in a state other than L0, retain sideband information until the one or more thresholds is reached, and send the sideband information to the host device upon reaching the one or more thresholds for a corresponding link state. The one or more thresholds correspond to a link state between the host device and the data storage device. The thresholds are either based on an amount of sideband information retained, a time of retaining sideband information, or a combination of the amount of sideband information retained and the time of retaining sideband information. The sideband information is retained and sent in a first-in first-out order.