Baseline Snapshot Refresh to Reduce Rehydration Amplification

Solution Overview

Problem

Existing data storage systems experience rehydration amplification during snapshot operations, leading to inefficiencies and increased latency.

Innovation Solution

Implementing an offload target mechanism that utilizes non-volatile RAM (NVRAM) as a buffer for data destined for storage drives, allowing direct-mapped flash storage systems to manage data blocks without additional address translation by storage controllers, and employing dual storage array controllers for failover and data management.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If traditional snapshot operations are performed in data storage systems, then data consistency can be maintained, but rehydration amplification occurs leading to increased latency and reduced efficiency

Engineering Contradiction:

Improvedata consistencyVSAvoidlatency

Core Design Contradiction:

ReliabilityVSLoss of time

Solution Approach 1:

The system performs preliminary actions by pre-computing and storing transformation metadata during snapshot creation. This metadata includes information about data block mappings and transformation requirements, which are then used during restoration to quickly reconstruct data without reprocessing the entire dataset, thereby reducing restoration latency while maintaining consistency

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The patent introduces an intermediary metadata storage layer that bridges the snapshot creation and restoration processes. This metadata storage contains transformation information and mapping data that mediates between the original data and the restored data, enabling efficient rehydration by avoiding direct reprocessing of all data blocks

Inventive Principle:

Principle #24Intermediary (Mediator)

2Reliability

If traditional snapshot operations are performed in data storage systems, then data consistency can be maintained, but rehydration amplification occurs leading to reduced operational efficiency

Engineering Contradiction:

Improvedata consistencyVSAvoidoperational efficiency

Core Design Contradiction:

ReliabilityVSProductivity

Solution Approach 1:

The system performs preliminary actions by pre-computing and storing transformation metadata during snapshot creation. This metadata includes information about data block mappings and transformation requirements, which are then used during restoration to quickly reconstruct data without reprocessing the entire dataset, thereby reducing restoration latency while maintaining consistency

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The patent introduces an intermediary metadata storage layer that bridges the snapshot creation and restoration processes. This metadata storage contains transformation information and mapping data that mediates between the original data and the restored data, enabling efficient rehydration by avoiding direct reprocessing of all data blocks

Inventive Principle:

Principle #24Intermediary (Mediator)

3Adaptability or versatility

If additional address translation is performed by storage controllers, then data management flexibility is improved, but system complexity increases

Engineering Contradiction:

Improvedata management flexibilityVSAvoidsystem complexity

Core Design Contradiction:

Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The patent introduces an intermediary metadata storage layer that bridges the snapshot creation and restoration processes. This metadata storage contains transformation information and mapping data that mediates between the original data and the restored data, enabling efficient rehydration by avoiding direct reprocessing of all data blocks

Inventive Principle:

Principle #24Intermediary (Mediator)

Solution Approach 2:

The patent extracts the address translation function from the storage controller and relocates it to the metadata storage system. By taking out this complex function from the controller, the system achieves better separation of concerns, reduces controller complexity, and enables more flexible data management through metadata-based addressing

Inventive Principle:

Principle #2Taking out (Extraction)

Data Source

PatentUS20260056844A1Reducing rehydration amplification in data storage systems

Publication Date: 2026.02.26 PURE STORAGE INC

AI summary

A data storage system may include a memory that stores instructions and one or more processors configured to execute the instructions to perform a process that includes 1) monitoring a storage system configured to store snapshots that include snapshot delta data representing changes relative to previous snapshots of the dataset; 2) detecting that a quantity of data written to the storage system has exceeded a threshold quantity of data written since writing a previous baseline snapshot of the dataset to the storage system; 3) generating, in response to detecting that the quantity of data written has exceeded the threshold quantity, a new baseline snapshot of the dataset; and 4) writing the new baseline snapshot to the storage system. Various other systems, methods, and computer program products are also disclosed.