Building The Default x86_64 Linux Kernel In Just 16 Seconds

[discordian]

It's not a matter of "not heard of", but rather trying to be realistic - how many people actually build in tmpfs?

You can build outside tmpfs?

All buildslaves I setup build in tmpfs, debian packages can be built in tmpfs (and their wiki documents how: https://wiki.debian.org/sbuild#sbuild_overlays_in_tmpfs). With eclipse I add a link to /tmp/x.y.z/build (/tmp - as you might have gueesed - is a tmpfs), eclipse will automatically create the folder is missing.
The only downside would be missing RAM, if the linker step needs alot of it...

[Michael]

Can't believe Michael hasn't heard about building applications in RAM. It didn't make sense with older machines, but now even most desktops have sufficient RAM for building large projects such as the kernel in RAM. The sources require around 1 GB, and the resulting binaries also need 1-2 GB. While compiling, each gcc thread probably uses few hundred megabytes at most. So, 32 GB might be enough for building on a 64 core system.

It's not a matter of "not heard of", but rather trying to be realistic - how many people actually build in tmpfs?

[caligula]

What about building in tmpfs? ;-)

Can't believe Michael hasn't heard about building applications in RAM. It didn't make sense with older machines, but now even most desktops have sufficient RAM for building large projects such as the kernel in RAM. The sources require around 1 GB, and the resulting binaries also need 1-2 GB. While compiling, each gcc thread probably uses few hundred megabytes at most. So, 32 GB might be enough for building on a 64 core system.

[programmerjake]

Now you can checkout the Linux master branch, compile the kernel and kexec into it from initrd. All while still booting faster than many systems.
Rolling release was yesterday, now it's run-from-source!

tcc was able to boot from the linux source about 15 years ago: https://bellard.org/tcc/tccboot.html

[rbanffy]

Has anyone tried that with a last-generation Xeon Phi? 72 relatively slow cores but 4 threads per core and 16 GB of HBM should give some interesting results.

[tchiwam]

And redirect all outputs to /dev/null or a file on tmpfs

[darkbasic]

Optane vs tmpfs would be REALLY interesting to see!

[discordian]

I'm almost certain there is like a category of languages which do something like that... What's the name again?

Binaries! You edit their source in a Hexeditor.

[AsuMagic]

Now you can checkout the Linux master branch, compile the kernel and kexec into it from initrd. All while still booting faster than many systems.
Rolling release was yesterday, now it's run-from-source!

I'm almost certain there is like a category of languages which do something like that... What's the name again?

[discordian]

Now you can checkout the Linux master branch, compile the kernel and kexec into it from initrd. All while still booting faster than many systems.
Rolling release was yesterday, now it's run-from-source!