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1. Ludovic Courtès (civodul@toot.aquilenet.fr)'s status on Tuesday, 08-Mar-2022 17:38:58 UTC Ludovic Courtès

   TIL (in a talk on RISC-V) that, since 1978, the x86 ISA got three new instructions *per month*.

   • Santa Claes 🇸🇪🇭🇰🎅 likes this.
   • Santa Claes 🇸🇪🇭🇰🎅 (clacke@libranet.de)'s status on Tuesday, 08-Mar-2022 17:39:03 UTC Santa Claes 🇸🇪🇭🇰🎅

     in reply to

     • Ekaitz Zárraga 👹
     @ekaitz_zarraga @civodul This is the major original selling point of gentoo.
   • Ludovic Courtès (civodul@toot.aquilenet.fr)'s status on Tuesday, 08-Mar-2022 17:39:04 UTC Ludovic Courtès

     in reply to

     • Ekaitz Zárraga 👹

     @ekaitz_zarraga I suspect the new instructions mostly come from extensions, in particular SIMD extensions since ~2000 (remember MMX? :-)).

     They trickle in slowly as people update their hardware and software.

     See also: https://hpc.guix.info/blog/2022/01/tuning-packages-for-a-cpu-micro-architecture/

   • Ekaitz Zárraga 👹 (ekaitz_zarraga@mastodon.social)'s status on Tuesday, 08-Mar-2022 17:39:04 UTC Ekaitz Zárraga 👹

     in reply to

     @civodul Finally I got the time to read the article. Really interesting work here!
     It's basically what I meant... so apt and friends can't really compile with the tuning we have on guix right? So you have to compile everything yourself to make it use the modern instructions...
     What a shame.

   • Ekaitz Zárraga 👹 (ekaitz_zarraga@mastodon.social)'s status on Tuesday, 08-Mar-2022 17:39:05 UTC Ekaitz Zárraga 👹

     in reply to

     @civodul I wonder how do package managers deal with that... we just don't really use the newest instructions, right?

   • Ekaitz Zárraga 👹 (ekaitz_zarraga@mastodon.social)'s status on Tuesday, 08-Mar-2022 17:39:06 UTC Ekaitz Zárraga 👹

     in reply to

     @civodul just search in the web a graph of instructions per year and you'll be surprised.

   • Santa Claes 🇸🇪🇭🇰🎅 (clacke@libranet.de)'s status on Wednesday, 09-Mar-2022 00:24:22 UTC Santa Claes 🇸🇪🇭🇰🎅

     in reply to

     • Ekaitz Zárraga 👹
     @ekaitz_zarraga @civodul Yet another argument for JITted languages!
     
     But I also think I read rather recently about tooling to support fat binaries that would contain native code for multiple sub-architectures and choose implementation at runtime.
   • Santa Claes 🇸🇪🇭🇰🎅 (clacke@libranet.de)'s status on Wednesday, 09-Mar-2022 00:25:28 UTC Santa Claes 🇸🇪🇭🇰🎅

     in reply to

     • Ekaitz Zárraga 👹
     • ghostdancer
     @ekaitz_zarraga @civodul @ghostdancer After finishing reading about the DEBIAN/ directory and the control files you can read about rpm specs. =)
   • Ekaitz Zárraga 👹 (ekaitz_zarraga@mastodon.social)'s status on Wednesday, 09-Mar-2022 00:25:29 UTC Ekaitz Zárraga 👹

     in reply to

     • ghostdancer

     @ghostdancer now i'm reading about how are those packages defined and I don't even care about it because my machine runs guix... oh god...
     @civodul

   • Ekaitz Zárraga 👹 (ekaitz_zarraga@mastodon.social)'s status on Wednesday, 09-Mar-2022 00:25:31 UTC Ekaitz Zárraga 👹

     in reply to

     • ghostdancer

     @ghostdancer @civodul And how do they do that?
     apt packages are precompiled so there must be some kind of source compilation automation... how is that defined? bash scripts?

   • ghostdancer (ghostdancer@mastodon.sdf.org)'s status on Wednesday, 09-Mar-2022 00:25:31 UTC ghostdancer

     in reply to

     • Ekaitz Zárraga 👹

     @ekaitz_zarraga apt-build downloads Debian source packages, not the binary common ones, and compiles them locally, I guess it gets the architecture and options from system information. It's similar to Gentoo but only the packages you want and debianized @civodul

   • ghostdancer (ghostdancer@mastodon.sdf.org)'s status on Wednesday, 09-Mar-2022 00:25:34 UTC ghostdancer

     in reply to

     • Ekaitz Zárraga 👹

     @ekaitz_zarraga @civodul I guess is good for some specific applications you may need the extra punch but not for the whole system.

   • ghostdancer (ghostdancer@mastodon.sdf.org)'s status on Wednesday, 09-Mar-2022 00:25:35 UTC ghostdancer

     in reply to

     • Ekaitz Zárraga 👹

     @ekaitz_zarraga @civodul In Debian you have apt-build, that downloads the Debian source packages ad compiles them optimized for your architecture, never used and don't know how optimized it is.

   • Ludovic Courtès (civodul@toot.aquilenet.fr)'s status on Wednesday, 09-Mar-2022 13:53:53 UTC Ludovic Courtès

     in reply to

     • Ekaitz Zárraga 👹
     • Santa Claes 🇸🇪🇭🇰🎅

     @clacke @ekaitz_zarraga True! The difference I think is that Gentoo makes reproducibility and provenance tracking harder because of that.

     Santa Claes 🇸🇪🇭🇰🎅 likes this.
   • Ludovic Courtès (civodul@toot.aquilenet.fr)'s status on Wednesday, 09-Mar-2022 13:57:23 UTC Ludovic Courtès

     in reply to

     • Ekaitz Zárraga 👹
     • Santa Claes 🇸🇪🇭🇰🎅

     @clacke @ekaitz_zarraga Yes, https://hpc.guix.info/blog/2018/01/pre-built-binaries-vs-performance/ talks about “fat binaries” and function multi-versioning, which are like you describe.

     Santa Claes 🇸🇪🇭🇰🎅 likes this.
   • Santa Claes 🇸🇪🇭🇰🎅 (clacke@libranet.de)'s status on Wednesday, 09-Mar-2022 13:58:25 UTC Santa Claes 🇸🇪🇭🇰🎅

     in reply to

     • Ekaitz Zárraga 👹
     @civodul @ekaitz_zarraga This is exactly it. I don't recognize all the terms, so if I got it from this article I must have just skimmed.