post type
Conceptual, architectural explainers — how a subsystem actually works underneath.
Each WSL2 distro's filesystem lives inside a dynamically-expanding .vhdx file on your Windows drive. It grows automatically as you use it — but deleting files inside WSL doesn't shrink it back down, and that's expected, not a bug.
Training a machine learning model inside WSL2 using your actual GPU sounds like it shouldn't work through a virtual machine layer at all. Here's the specific virtualized GPU mechanism that makes it possible.
For years, WSL distros ran without systemd — meaning services expecting it simply failed. Here's why that gap existed, and what changed architecturally to finally close it.
Installing Ubuntu via the Microsoft Store feels like installing any other app. Underneath, WSL distros are root filesystem tarballs registered with a small platform layer — and that model is what makes import/export and custom distros possible.
WSL2's lightweight VM claims memory dynamically as Linux processes need it — but historically gave that memory back to Windows only reluctantly. Here's what's actually happening, and what you control via .wslconfig.
Running notepad.exe from a Bash prompt, or a Linux tool from Windows' own command line, works because of a specific interop layer translating between two completely different executable formats and process models.
Running a Linux GUI application inside WSL and having its window appear alongside your native Windows apps looks like magic. It's actually a full Wayland compositor and audio system, tunneled over RDP, running invisibly.
WSL2's original networking design put it behind its own virtual network, invisible to the rest of your LAN by default. Mirrored networking mode, added later, takes a fundamentally different approach — and each has real tradeoffs.
Linux and Windows filesystems handle permissions, case sensitivity, and paths in fundamentally different ways. WSL's cross-OS file access works by translating between them at the protocol level — and that translation has real performance costs.
WSL2 doesn't borrow a distro's kernel — Microsoft maintains its own fork, patched specifically for the virtualized environment WSL2 runs in, and ships it independently of both Windows and any Linux distro's own kernel.