alt Hacker NewsEvery time you run `wsl --install <distro>` you are creating a new VM. Every time you run `wsl --unregister <instance id or name/>` your are removing a VM.
It is these two operations at the heart of OP's app.
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This is not true - it's actually all the same VM if you check hcsdiag.
WSL2 distros only use Linux namespaces, same as docker, and the WSL2 --system distro can see PIDs from all running WSL2 distros.
Okay, are you guys using wrong terminology? Are you talking about a filesystem image as a "VM", because that would not be correct. A "Virtual HD" (VHD) is not a VM. Do you think a WSL2 distro instance is a "VM" because it's persistent? Did you know Docker containers can be persistent as well, people just choose as a best practice not to use it like that? Does that make them magical VMs?
WSL2 has a single VM running as the process vmmem (or vmmemWSL in the newest versions). This is the single Linux kernel that will be shared by every WSL2 instance. It will also be the instance that hosts Docker containers as well. I mean, I'm just echoing myself and apologies for the repetition, but this is just easily confirmed, utter factual truth.
A rootfs is not a VM. WSL2 and containers have different nuances about their filesystem and isolation (WSL2 instances is aware of other instances, for instance, as a design aspect, and WSL2 persists rootfs changes while docker as a best practices does not), but they're more alike than different. And they share little in common with something like VirtualBox or vmware, which actually isolate every such system as VMs.
Again, sigh, if you install 10 WSL2 "distros", you will have 10 rootfs overlays on your drive, and 10 persistence VHD files. When you run these the VM they all run under in the shared vmmem instance, which is the single utility Linux VM.
No, this is wrong.
WSL2 distributions share the same Linux kernel. They only get their own root filesystem with a Linux userland (/bin, /usr, /lib etc), and some WSL config meta data. This is then stored as a virtual disk image (which is probably where your belief comes from). But the kernel runs in a single utility VM. The distros share that kernel instance and they are separated via namespaces only.
This makes running multiple WSL2 distributions in parallel very performant btw, as there is no world switch.