Performance Benchmarks: DuoBolt vs Czkawka, dupeGuru & Gemini 2

DuoBolt delivers exceptional performance in real-world duplicate file detection scenarios. These benchmarks compare DuoBolt against three leading alternatives: Czkawka, dupeGuru, and Gemini 2.

All tests were performed on Apple Silicon M1 Pro hardware running macOS Tahoe 26.1 with identical configurations, cleared caches, and back-to-back execution to ensure fair comparisons.

Performance Overview

Up to 20× faster

DuoBolt achieves up to 20× faster scan times on local files compared to competing tools, finishing jobs where others slow down or time out.

1.2–1.4× on NAS

On network-attached storage with warmed caches, DuoBolt maintains a 1.2–1.4× performance advantage over competitors.

Handles 1+ TB datasets

DuoBolt successfully scans terabyte-scale datasets while maintaining speed and accuracy, even when competitors time out.

Detailed Benchmark Results

The following table shows measured scan times (in seconds) across five real-world datasets. Lower times are better. Timeout indicates the tool exceeded 15 minutes without completing. Failed indicates permission errors or crashes.

Design Projects (13.17 GB)

Tool	Time	Speedup vs DuoBolt
DuoBolt	1s	—
Czkawka	1s	1.0×
dupeGuru	11s	11.0×
Gemini 2	5.5s	5.5×

Dataset: 13.17 GB of Sketch and Figma export files Result: DuoBolt and Czkawka tie on small, uniform datasets. DuoBolt pulls ahead significantly as complexity increases.

Codebase (37.92 GB)

Tool	Time	Speedup vs DuoBolt
DuoBolt	3s	—
Czkawka	4s	1.3×
dupeGuru	63s	21.0×
Gemini 2	17s	5.7×

Dataset: 37.92 GB across three code directories (21.13 GB, 13.61 GB, and 3.18 GB web apps) Result: DuoBolt’s multi-core parallelism shines on diverse file structures, completing in 3 seconds while dupeGuru takes over a minute.

Codebase + Library (Large)

Tool	Time	Speedup vs DuoBolt
DuoBolt	24s	—
Czkawka	55s	2.3×
dupeGuru	Timeout	—
Gemini 2	Failed	—

Dataset: Codebase plus macOS user Library (~/Library) directory Notes:

dupeGuru timed out before completion
Gemini 2 lacked permission for ~/Library

Result: DuoBolt handles complex permission scenarios and large file counts where competitors fail or time out.

NAS Cold (1.01 TB, Spun-Down Disks)

Tool	Time	Speedup vs DuoBolt
DuoBolt	64s	—
Czkawka	85s	1.3×
dupeGuru	142s	2.2×
Gemini 2	Timeout	—

Dataset: 1.01 TB Synology NAS (DS920+) snapshot with cold, spun-down disks Breakdown: 605 GB video, 246 GB photos, 162 GB music Result: DuoBolt’s streaming I/O and BLAKE3 parallelism maintain speed even on slow, cold network drives.

NAS Warm (1.01 TB, Warmed Cache)

Tool	Time	Speedup vs DuoBolt
DuoBolt	20s	—
Czkawka	24s	1.2×
dupeGuru	59s	3.0×
Gemini 2	Timeout	—

Dataset: 1.01 TB Synology NAS snapshot with warmed cache Breakdown: 605 GB video, 246 GB photos, 162 GB music Result: With caches warm, DuoBolt completes in 20 seconds while dupeGuru still requires nearly a minute.

Methodology

All benchmarks follow strict testing protocols to ensure fair, reproducible results:

Test Environment

Hardware: Apple Silicon M1 Pro processor
OS: macOS 26.1 (Tahoe)
NAS: Synology DS920+ with 3 HDD drives installed
Network: Gigabit Ethernet connection

Test Conditions

All caches cleared between runs
Identical include/exclude rules applied across all tools
Back-to-back execution on the same machine
No other intensive processes running during tests
Tools configured for maximum performance (default settings where applicable)

Tool Configurations

Gemini 2 ran in duplicates-only mode (similarity detection disabled for fair comparison)
All tools used their default hash algorithms
dupeGuru and Gemini 2 timed out on NAS datasets (15-minute timeout limit)
Gemini 2 encountered permission errors on ~/Library directory

Measurement

Scan times measured from start to completion
Times rounded to nearest second for readability
Timeout threshold: 15 minutes (900 seconds)
Only successful, complete scans included in timing comparisons

Why DuoBolt Is Faster

DuoBolt’s performance advantage comes from several architectural decisions:

Multi-Core Parallelism

DuoBolt keeps all CPU cores busy with per-root parallelism and BLAKE3 worker hashing, instead of processing files sequentially. This approach scales efficiently across modern multi-core processors.

Streaming I/O

Chunked, streaming reads overlap disk/NAS I/O with hashing operations, hiding latency on slower disks or remote drives. This design ensures CPUs never sit idle waiting for data.

BLAKE3 Hashing

BLAKE3 is a modern, cryptographically secure hash function optimized for speed and parallelism. It significantly outperforms older algorithms like SHA-256 or MD5 while maintaining collision resistance — see the full BLAKE3 in DuoBolt page for the algorithm comparison and how DuoBolt applies it.

Smart Prehashing

The default head+tail prehash filters candidates efficiently before full hashing, reducing unnecessary work on large datasets. Full-content hashing still occurs for matched candidates, ensuring accuracy remains perfect.

Unified Engine

Desktop and CLI share the same high-performance engine, so both interfaces inherit these optimizations without compromising accuracy or features.

Core Concepts

Learn how DuoBolt’s engine works under the hood, including hashing, prehashing, and parallelism strategies.

Read Core Concepts →

CLI Usage

Automate benchmark-quality scans using the DuoBolt CLI for scripting and integration.

Read CLI Usage →

FAQ

Common questions about performance, accuracy, and optimization.

Read FAQ →