41–50 of 61 posts
Curious: how do people use Qemu the most these days? Dev environment? Running specific apps on a different OS? I don't know... gaming?
I'm curious if QEMU will ever support features like x86(_64) hardware paths that with Arm and RISC-V... Since most of the patents are now expired, it makes a lot of sense. Apple seems to be further along here than other competitors, but it seems to be limited to Rosetta, not broadly supported.
QEMU is truly excellent software, from the perspective of a person who very rarely needs to emulate another architecture. It "just works" and has wonderful integrations with basically everything I could want.. sometimes it feels like magic: even if the commandline UX is a bit weird in places. I've always wondered though how it works with KVM: I know KVM is a virtualisation accelerator that enables passing through nat…
> I've always wondered though how it works with KVM Other people have given some more comprehensive explanations, but I'll try to put it as simply as possible. Plain QEMU has a CPU emulation layer called TCG. The machine basically consists of memory (RAM and MMIO devices) and CPUs (CPU registers and state). When QEMU has set up the machine and is ready to run, it calls TCG to say "given this memory and this initial C…
QEMU is truly excellent software, from the perspective of a person who very rarely needs to emulate another architecture. It "just works" and has wonderful integrations with basically everything I could want.. sometimes it feels like magic: even if the commandline UX is a bit weird in places. I've always wondered though how it works with KVM: I know KVM is a virtualisation accelerator that enables passing through nat…
Not everything uses qemu. Some do. More use KVM. Not everything does. Example: https://firecracker-microvm.github.io/
QEMU is truly excellent software, from the perspective of a person who very rarely needs to emulate another architecture. It "just works" and has wonderful integrations with basically everything I could want.. sometimes it feels like magic: even if the commandline UX is a bit weird in places. I've always wondered though how it works with KVM: I know KVM is a virtualisation accelerator that enables passing through nat…
Xen is still used massively too.
Curious: how do people use Qemu the most these days? Dev environment? Running specific apps on a different OS? I don't know... gaming?
If you find yourself limited by the equivalent VPS expense, I discovered that for my use-case (mixed web hosting, dev services, self-hosting) I could squeeze a lot more out of an entry level bare-metal box with ~48GB of RAM, and everything just becomes a VM in Proxmox, and it's still trivially simple to scale/replicate, maintain backups, and tie together with other VPS or cloud services.
The only part that was a bit of a challenge is negotiating NAT for the virtual NICs so you don't need separate IPv4 addresses for each guest. But Proxmox's docs are pretty robust, and I'm sure there are dozens of tuts available now.
Curious: how do people use Qemu the most these days? Dev environment? Running specific apps on a different OS? I don't know... gaming?
- https://github.com/moby/buildkit/blob/v0.23.2/docs/multi-pla...
- https://github.com/moby/buildkit/blob/v0.23.2/Dockerfile#L16...
- https://github.com/tonistiigi/binfmt/blob/buildkit/v9.2.2-54...
- https://github.com/tonistiigi/binfmt/blob/buildkit/v9.2.2-54... and https://github.com/tonistiigi/binfmt/blob/buildkit/v9.2.2-54...
and let me tell you from first-hand experience, that trying to swap in an updated version of the bundled qemu binary when the static version panics on some mis-emulated instruction is some whooooooo, boy
Curious: how do people use Qemu the most these days? Dev environment? Running specific apps on a different OS? I don't know... gaming?
I'd suspect a great deal of people are secretly benefiting from qemu when they do $(docker build --platform linux/{arm64,amd64}) courtesy of binfmt_misc and a static copy of qemu - https://github.com/moby/buildkit/blob/v0.23.2/docs/multi-pla... - https://github.com/moby/buildkit/blob/v0.23.2/Dockerfile#L16... - https://github.com/tonistiigi/binfmt/blob/buildkit/v9.2.2-54... - https://github.com/tonistiigi/binfmt/blob…
I'm curious if QEMU will ever support features like x86(_64) hardware paths that with Arm and RISC-V... Since most of the patents are now expired, it makes a lot of sense. Apple seems to be further along here than other competitors, but it seems to be limited to Rosetta, not broadly supported.
If the kernel makes it available to userspace, then it could be done. I am not aware of any specific emulation-friendly extensions to RISC-V though.
QEMU is truly excellent software, from the perspective of a person who very rarely needs to emulate another architecture. It "just works" and has wonderful integrations with basically everything I could want.. sometimes it feels like magic: even if the commandline UX is a bit weird in places. I've always wondered though how it works with KVM: I know KVM is a virtualisation accelerator that enables passing through nat…
If you use it rarely, I can high recommend the excellent QuickEMU [0] Any VM is just a `quickget ubuntu 24.04` and `quickemu --vm ubuntu-24.04.conf` away. The conf file is just a yaml that is very readable and can give you more cores/ram/disk easily. Just run `quickget` to get a list of OS's to download. [0] https://github.com/quickemu-project/quickemu