[Date Prev][Date Next] [Thread Prev][Thread Next] [Date Index] [Thread Index]

Re: Increasing minimum 'i386' processor



Hello,

2011/11/23 Matthias Klose <doko@debian.org>:
> On 11/19/2011 11:42 PM, Ben Hutchings wrote:

>> (Later it should be increased
>> further, and eventually i386 should be reduced to a partial architecture
>> that may be installed on amd64 systems.)  This would allow the use of
>> optimisations and new instructions throughout userland that improve
>> performance for the vast majority of users.

> could you give numbers what kind of improvements you would expect?  The biggest
> burden for i386 is the register pressure, which you won't fix with targeting a
> newer processor.  The better approach would be a new port, the x32 architecture;
> I don't know if anybody did look into building a distribution for this
> architecture yet.  The next thing could be to default to sse2 math instead of
> x87 (didn't look if this is already the default for x32).

FWIW, Yocto has attempted to build an image for x32:
  <https://wiki.yoctoproject.org/wiki/X32_abi>
Yes, x32 defaults to SSE and improvements expected 7-10% on integer
math over ia32 (5-8% over intel64) and 5-11% on fp math over ia32.
Figures from
 <http://linuxplumbersconf.org/2011/ocw/system/presentations/531/original/x32-LPC-2011-0906.pptx>

Cheers,
-- 
 Héctor Orón  -.. . -... .. .- -.   -.. . ...- . .-.. --- .--. . .-.


Reply to: