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Comment by umvi | Hacker News Reader

When I launch my WSL2 Ubuntu shell, I have a CLI prompt in < 1 second. Clipboard works perfectly since it is a window similar to PowerShell, my windows file system is mounted in under /mnt, and generally everything is lighting fast.

Getting that same quality of experience under VirtualBox was nightmarish. Longer boot times, shared clipboard/filesystems were always breaking, random stuff related to hardening made update difficult.

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Other than the startup time (mitigated by starting the VM right after startup) I have no issues with virtualbox. File mounts, copy & paste... everything works more or less fine.

WSL, on the other hand, has been nothing but trouble.

One downside there is the constantly huge RAM consumption of such a setup.

EDIT: At least compared to WSL1. However WSL2 also has some advantages in that it can reclaim unused memory and suspend the VM when not in use.

Why would VM-based WSL2 use any less RAM?

WSL VMs are gen2 (fully paravirtual) hyper-v VMs, so use dynamic memory allocation. VirtualBox, even with Hyper-V as its engine, doesn't do this. I don't think any standalone Linux distros offer a standalone Hyper-V paravirtual image that is not a WSL2 image.

The Ubuntu image you can select in the "New VM" dialog in the Hyper-V management tool (or whatever it's called) absolutely does work with dynamic memory allocation and I seem to recall getting it to work on an Arch VM as well.

I believe the "Linux Integration Services" for Hyper-V are actually mainlined at this point so I would expect most things to work. Setting up RDP for enhanced desktop sessions is the only painful thing I remember.

You don't need paravirtualization to do dynamic memory allocation -- all VMs do this.

No. Gen1 images use a fixed allocation pool instead of an oversubscription model. You need a gen2 image with a cooperative memory allocator on the guest in order for this to work properly.

Well, so barring ancient HyperV versions, all VMs do it. This is more of a guest thing than hypervisor thing, anyway. All the VM needs to support is balloning and this is completely unrelated to paravirtualization.

>Clipboard works perfectly

Which one? Secondary? And the primary does not work at all?

The Windows clipboard just works, because WSL2 terminals are just regular Windows apps.

At this point - Can't you just SSH into the local linux VM or a remote linux server?

You can, but to get the same edit in the windows UI experience you would need sshfs, which is another nightmare thing to get running on Windows.

Primary and secondary selections are specific to X11 which is not involved at all when running WSL command line apps in a Windows terminal

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