2016-09-19 15:34 GMT+02:00 Allan McRae <allan@archlinux.org>:
On 19/09/16 23:14, Balló György via arch-dev-public wrote:
2016-09-19 7:02 GMT+02:00 Allan McRae <allan@archlinux.org>:
This goes beyond just adding SSE2 support.
Years ago, Arch Linux was "optimised for modern processors". These were the days when every other distro was using i386 and we had a blazingly fast i686 port. Now every other distro uses i686 while we have sat still. Even major software developments are starting to require SSE2. It is time we moved forward.
How can we achieve this? I see several options:
1) Do "nothing". Add a hook to the filesystem package that detects whether a system has SSE2 support and blocks installation of certain packages.
2) Add SSE2 to our optimisations and require "i686 + SSE2"
3) Move our minimum CPU to something less than 20 years old (even i786 would get us SSE2+3 instructions and is 15 years old)
4) We add more modern CPU builds (and set them automatically building once the base architecture is updated).
I am in favour of #3 for our 32-bit support. And that would be end of line as far as 32 bit support in this distribution goes.
(We may want to consider #4 for our x86_64, but that is another conversation).
Allan
I would not be happy with #3, because I still have two 13 years old systems with NetBurst-based CPUs without SSE3 support. But of course I don't use them in everyday use.
If we limit our choice based on your CPU, then we need to limit based on the other CPU mentioned in this thread.
That should not be a consideration at all. What we need to do is think about what make our distribution worthy of being a distribution. Original the selling points were rolling release, vanilla packages and optimised binaries. We have lost the latter. Do we want to get it back?
Another option could be to keep i686 and x86_64 as is, and introduce new architectures with automatically built optimised packages for i686 + SSE2 or SSE3, and for x86_64 + SSE4.2 or AVX. This is something similar to your option #4, but keeps the compatibility with all existing systems. -- György Balló Trusted User