x32 abi support?

[Matthew Garrett]

On Wed, May 16, 2012 at 09:18:32AM -0400, Neal Becker wrote:
> I noticed this article:
> 
> http://www.phoronix.com/scan.php?page=news_item&px=MTEwMTk
> 
> Has this been discussed on fedora?

x32 is mostly beneficial in that it reduces pointer size and so memory 
consumption, with the side benefit that it may also provide slightly 
higher performance due to being able to fit more in cache. But this is 
only true for a pure x32 system. If you have any applications that need 
to be 64-bit (ie, anything that is going to need more than 4GB of 
address space, which is very different from needing more than 4GB of 
RAM) then you need to have two copies of your libraries and suddenly 
your memory benefits have entirely vanished.

So, overall, x32 is only really beneficial for embedded platforms rather 
than general purpose ones. As Josh says, if there's sufficient interest 
then it could potentially be implemented as a separate architecture and 
spend some time in secondary, but I don't know that there'd be a huge 
benefit to Fedora to spend much time on it.

-- 
Matthew Garrett | mjg59 at srcf.ucam.org