WSL2 ext4.vhdx Won't Shrink: What Actually Works in 2026 (Sparse VHD, diskpart, fstrim — All Measured)
Measured on: Windows 11 Home 10.0.26200 · WSL 2.7.3.0 (kernel 6.6.114.1-1) · Ubuntu 26.04 LTS (fresh install) · 2026-08-06 · every size below read from the actual ext4.vhdx, both logical size and size-on-disk The problem My research distro once grew to ~47 GB — conda environments, Hugging Face caches, PyTorch checkpoints. I deleted files inside WSL, watched df -h drop, and the ext4.vhdx on the Windows side did not give back a single byte. Back then I gave up and nuked the whole distro with wsl --unregister. ...