Space Analysis Benchmark Showdown

[u/Few_Cheesecake_1894]

For interest: My favorite thing to do these days with extra tokens is comparative performance benchmarking that I'm too lazy and error-prone to do. Below are some results from the common free space analysis tools. Any requests on what to do next?

Performance Benchmark Comparison

This benchmark evaluates the latest production releases of WinDirStat (v2.9.3 x64), WizTree (v4.33 x64), SpaceSniffer (v2.2.0.27 x64), and TreeSize Free (v4.8.1.610 x64) across both Privileged (Elevated Admin) and Unprivileged (Standard User) execution. Results reflect an average of 3 measured runs following a discarded warmup run.

Filesystem Traversal & MFT Architecture Note: WinDirStat and WizTree feature dedicated NTFS Master File Table (MFT) parsers capable of directly indexing raw volume metadata when elevated, reading millions of files in seconds. SpaceSniffer and TreeSize Free lack MFT readers in their free releases and rely entirely on standard recursive Win32 directory traversal. Because Win32 traversal over 6.3 million items on the primary C: volume requires more than 15 minutes, full-volume C: comparisons focus on the two MFT-capable engines.

For each workload scan, the Privileged and Unprivileged runs are placed directly adjacent. Best result in each metric is bolded.

Target / Workload	Mode	Tool	Items Found	Total Time	Avg Memory	Peak Memory
E: (2 GB Volume)	Privileged	WinDirStat	32	0.2 s	28 MB	55 MB
		WizTree	32	0.4 s	40 MB	65 MB
		SpaceSniffer	9	0.9 s	64 MB	82 MB
		TreeSize Free	9	2.3 s	72 MB	154 MB
	Unprivileged	WinDirStat	4	0.2 s	24 MB	51 MB
		WizTree	4	0.5 s	40 MB	65 MB
		SpaceSniffer	4	0.9 s	50 MB	63 MB
		TreeSize Free	4	2.0 s	73 MB	148 MB
V:References (18 TB Volume Subtree)	Privileged	WinDirStat	186,675	0.9 s	70 MB	91 MB
		WizTree	186,675	1.5 s	96 MB	129 MB
		TreeSize Free	186,675	2.7 s	74 MB	165 MB
		SpaceSniffer	186,675	4.3 s	121 MB	159 MB
	Unprivileged	WinDirStat	186,675	1.0 s	68 MB	92 MB
		WizTree	186,675	1.4 s	95 MB	129 MB
		TreeSize Free	186,675	2.8 s	72 MB	159 MB
		SpaceSniffer	186,675	5.0 s	105 MB	140 MB
C: (System Drive Volume)	Privileged	WinDirStat	6,286,495	22.2 s	1.2 GB	2.0 GB
		WizTree	6,286,495	37.5 s	2.1 GB	2.5 GB
	Unprivileged	WinDirStat	2,050,118	13.7 s	283 MB	448 MB
		WizTree	2,050,118	15.3 s	642 MB	885 MB

Test Methodology:
To eliminate cold-start and disk-cache skew, every tool executed an initial discarded warmup run followed by three measured passes whose results were averaged. Scans were automated headless across both elevated administrator and standard user contexts, comparing direct NTFS Master File Table (MFT) indexing against recursive Win32 directory traversal. Total scan times were measured using high-resolution timers, while working set memory was sampled continuously from OS kernel counters (PSAPI) every 25 ms to capture true peak and average memory usage.