alt Hacker NewsI... fail to see the point of running just one process.
If it's just a PoC, then:
1) I remember seeing a linux firewall/gateway set up to run with just the kernel, without any userspace at all. Completely unhackable.
2) To print some text or run a simple program, I belive DOS without a memory manager would be even faster.
3) It takes 1s to boot linux, but an ordinary PC takes 10s to get to that linux. Even U-boot on ARM takes some seconds to load a kernel.
BTW, if anyone knows any current platform that can XiP a linux kernel, please share.
Replies
> I... fail to see the point of running just one process.
It makes sense if you got some legacy piece of hardware that has extremely limited resources, both in terms of RAM and storage. Write your code in Go and you don't even need libc any more.
Wouldn't this be useful for embedded types of applications where you have a very specific task you want to do and you want to do it now.... like that firewall example?
Embedded devices or other SoC situations, certain limited scope situations where docker is undesirable/unnecessary, etc.
> I remember seeing a linux firewall/gateway set up to run with just the kernel, without any userspace at all. Completely unhackable.
Do you remember any details that would let me search for it? Because that does sound cool, and even maybe useful; the thought has certainly crossed my mind that a router or VPN box doesn't really get a lot of use out of userspace... Although maybe it's worth keeping for control/configuration/debugging.
> To print some text or run a simple program, I belive DOS without a memory manager would be even faster.
Or just make your code boot directly. It's not hard to make a .efi, or use https://github.com/jart/cosmopolitan to make a binary that runs in many places including bare metal.