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Reclaim Docker and WSL Disk Space on Windows

Docker prune, compose cleanup, VHDX compact, and WSL package caches: safe reclamation from DupeZappa's Cleanup Center.

  • cleanup
  • docker
  • wsl
  • windows

Docker Desktop and WSL2 eat disk space quietly. Old images, build cache, and growing ext4.vhdx files can cost tens of gigabytes while your photo library gets blamed.

DupeZappa Cleanup Center includes Container Space and WSL Space tabs for preview-oriented reclamation on dev machines, not routine docker system prune -a without looking.

Docker: what grows

Artifact Typical cause
Unused images Abandoned tags after refactors
Build cache Repeated docker build without prune
Stopped containers Forgotten one-off runs
Compose projects Orphaned volumes

Cleanup Center surfaces Docker disk usage and offers prune actions with visibility; review what will be removed before confirming.

WSL: what grows

Artifact Typical cause
ext4.vhdx Package caches, npm/pip inside distro
Distro package managers apt, dnf caches per distro
Quarantine folders Failed moves inside Linux FS

WSL Space tab reports per-distro usage and targets package caches. VHDX compact may require manual steps when Windows has not auto-trimmed; DupeZappa documents the workflow in-app. Shut down WSL before compact operations.

Safe order of operations

  1. Disk Usage: confirm Docker/WSL is actually the hog vs Downloads duplicates.
  2. Container Space: prune unused images you can re-pull from registry.
  3. WSL Space: clear package caches inside distros you still use.
  4. VHDX compact: only after backups; not interchangeable with duplicate delete.

Do not conflate VHDX shrink with deleting duplicate ISOs in Downloads; they are different problem classes.

Related Cleanup Center tabs

Developers often pair this pass with:

  • Package Managers: npm, pnpm, pip, Go module cache, NuGet, uv, Poetry, Conda, Scoop, Chocolatey.
  • Project Space: build artifacts in old repos.
  • Windows Tools: Storage Sense, DISM, installer caches.

All follow preview-first cleanup; see Preview-First Cleanup.

When not to automate

  • Shared Docker volumes with databases you have not exported.
  • WSL distros you have not booted in a year but still contain the only copy of work.

Export or backup before aggressive prune. Cleanup Center is for reclaimable cache, not archive policy.

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