[Debian-ppc64-devel] I am planning to restart ppc64 ports project.

[Thibaut VARÈNE]

Le 4 oct. 10 à 14:11, Hector Oron a écrit :

> Hello,
>
> 2010/10/4 Thibaut VARENE <varenet at debian.org>:
>> Here are some pointers if you care:
>> http://www.yellowdog-board.com/viewtopic.php? 
>> f=4&t=3098&p=11887#p11892
>
> Indeed, this seems to be true for all 64 bit machines, but x86_64

not exactly, at least not exactly to the same extent this impacts PPC.

> where extra registers were designed to help improve speed up, but

yes there is a major perf gain in running x86_64 vs x86_32. That's  
what leads most people in believing this is always true, when it's not.

> quite painful. I do wonder why don't we all run 32-bit userlands
> (sparc is a case where upstream is going 64-bit only)

one of the very few.
Sparc going 64bit only is mostly a "SPARC V9 ABI"-only support move.  
Sparc is one of the cases where there are actual advantages in running  
full 64-bit userland.

I suggest reading http://docs.sun.com/app/docs/doc/816-5138/6mba6ua5r?l=en&a=view 
  among other things.

> our instruction cache performance and provide optimized libraries for
> the particular cases without having to bootstrap yet another port.
>
> Would it make sense to you to work on multiarch[1] approach for
> providing 64-bit libraries when those are needed (in PPC64 particular
> case?)

It certainly would. Actually, I believe this is the Right Thing (TM)  
to do ;)

HTH

-- 
Thibaut VARÈNE
http://www.parisc-linux.org/~varenet/