Data Segment Sketching for Memory-Efficient Inline Deduplication

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional data deduplication techniques struggle to handle large-scale data reduction efficiently, particularly for enterprise applications, due to the computational burden and memory requirements of generating and comparing fingerprints for data chunks, making them impractical for petabyte-scale data management.

Innovation Solution

The use of sketches to characterize large data segments, comparing these sketches for similarity, and performing differencing operations only when necessary, reduces memory and computational demands by generating pointers for groups of matching chunks instead of individual chunks.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Loss of substance

If conventional fingerprint-based deduplication techniques are used to identify and eliminate duplicate data chunks, then data reduction capability is improved, but memory consumption and computational burden increase significantly

Engineering Contradiction:
Improvedata reduction ratioVSAvoidmemory consumption
Core Design Contradiction:
Loss of substanceVSQuantity of substance

Solution Approach 1:

The patent divides data into fixed-size chunks and uses probabilistic counting sketches to represent each chunk's fingerprint information. Instead of storing complete fingerprints for all chunks, the system segments the deduplication process into chunk-level processing with compact sketch representations, reducing memory consumption while maintaining deduplication capability.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent transforms the representation of data chunk fingerprints from exact hash values to probabilistic counting sketches. This parameter change allows the system to approximate fingerprint matching with significantly reduced memory requirements, trading exact precision for scalable memory efficiency in handling large-scale data deduplication.

Inventive Principle:
Principle #35Parameter changes

2Measurement precision

If complete fingerprint comparison is performed for every data chunk to ensure accurate deduplication, then deduplication accuracy is improved, but processing time increases

Engineering Contradiction:
Improvededuplication accuracyVSAvoidprocessing time
Core Design Contradiction:
Measurement precisionVSLoss of time

Solution Approach 1:

The patent performs partial fingerprint comparison using counting sketches instead of complete fingerprint verification for all chunks. The system uses probabilistic matching to identify potential duplicates quickly, then performs more rigorous verification only when necessary, reducing overall processing time while maintaining acceptable deduplication accuracy.

Inventive Principle:
Principle #16Partial or excessive action

Solution Approach 2:

The patent uses lightweight, disposable counting sketch structures that can be rapidly created and compared. These temporary sketch representations serve as efficient proxies for complete fingerprints, enabling fast preliminary comparisons without the computational overhead of full fingerprint verification for every data chunk.

Inventive Principle:
Principle #27Cheap short-living objects (Disposable)

3Loss of substance

If an index table is generated to store all data chunk fingerprints for deduplication, then deduplication functionality is improved, but system complexity and memory overhead increase

Engineering Contradiction:
Improvedata reduction capabilityVSAvoidsystem complexity
Core Design Contradiction:
Loss of substanceVSDevice complexity

Solution Approach 1:

The patent extracts only the essential fingerprint information from complete data chunks and stores it in compact counting sketch structures. Instead of maintaining comprehensive index tables with full fingerprint details, the system extracts and stores only the necessary probabilistic representation, simplifying the overall system architecture while preserving deduplication functionality.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The patent creates simplified copies of fingerprint information in the form of counting sketches. These sketch copies serve as lightweight proxies that capture the essential characteristics needed for deduplication without replicating the full complexity of original fingerprint data structures, reducing system complexity and memory overhead.

Inventive Principle:
Principle #26Copying

Data Source

PatentEP4078340B1Systems and methods for sketch computation
Publication Date: 2025.10.22 NDATA INC
  • EP4078340B1 patent drawingFigure 1
  • EP4078340B1 patent drawingFigure 2
  • EP4078340B1 patent drawingFigure 3

AI summary

A method for sketch computation is provided. The method may comprise receiving an input data stream from one or more client applications. The method may also comprise generating at least one segment from the input data stream. At least one segment may comprise a plurality of chunks. The method may further comprise computing a sketch of the at least one segment. The sketch may comprise a set of features that are representative of or unique to the at least one segment, such that the set of features corresponds to the at least one segment. The sketch may be useable for inline deduplication of at least one other input data stream received from the one or more client applications without (i) generation of a full index of the plurality of chunks or (ii) comparison of the at least one other input data stream to the full index.