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by jcalvinowens 8 days ago
> The build takes about 30-45 minutes

If you don't actually need all the drivers, you can use "make localmodconfig" to substantially reduce that. My local kernels build in 90 seconds on a 32-thread desktop machine :)

The kernel is a lot more stable than people think: I run the daily linux-next on my Debian stable gaming PC to look for bugs, and I don't find very many.
2 comments
tredre3 7 days ago
You're being a bit disingenuous, it builds in 90 seconds because you build it daily and the vast majority of objects are unchanged and cached by ccache.
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chlorion 7 days ago
No, I don't think that's what happening actually.

A stripped down cold build will literally take 90 seconds without caching on modern hardware.

The overwhelming majority of stuff that is being built is drivers, and most of them probably aren't needed for any specific user, so you can disable quite a lot of stuff.

Fwiw a full build of the fedora kernel config takes around 5-10m for my 12core ryzen 3900x, and it's definitely not the fastest CPU around.

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jcalvinowens 7 days ago
No, 90 seconds is the clean build time without ccache.
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wolfi1 7 days ago
try to build it with make clean first
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jcalvinowens 7 days ago
It's actually faster than I remembered:

  {0}[calvinow@sousa ~/git/linux] git describe
  v7.1
  {0}[calvinow@sousa ~/git/linux] git clean -dffxq
  {0}[calvinow@sousa ~/git/linux] zcat /proc/config.gz > .config
  {0}[calvinow@sousa ~/git/linux] time make -skj32 tar-pkg
  './System.map' -> 'tar-install/boot/System.map-7.1.0'
  '.config' -> 'tar-install/boot/config-7.1.0'
  './vmlinux' -> 'tar-install/boot/vmlinux-7.1.0'
  'arch/x86/boot/bzImage' -> 'tar-install/boot/vmlinuz-7.1.0'
  
  real    0m56.539s
  user    18m41.863s
  sys     2m8.754s
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