Tomas Mraz wrote:
On Thu, 2005-06-09 at 10:15 -0400, Dan Williams wrote:
The question, distilled:
Would you like: (a) Small speed hit for Opteron users, OR (b) much
larger speed hit for EM64T users?
The question is how small is the small hit and how large is the large
one. Percentage numbers anyone?
I have an old data for gcc3.4. Data should be practically the same for
gcc4 because tuninng affect back back end optimizations which have not
been changed since gcc3.4.
In brief, when we use tuning to AMD64, SPECFP2000 (floating point
programs) is 28% worse and SPECINT2000
(integer benchmarks) is 0.6% worse on Intel nocona processor.
When we use tuning to Intel Nocona, SPECFP2000 is 2.7% and SPECINT2000
is 1.6% worse on Opteron.
Code tuned for Intel Nocona parctically always has smaller size.
So I think tunning to nocona by default is a right decision.
--
fedora-devel-list mailing list
fedora-devel-list@xxxxxxxxxx
http://www.redhat.com/mailman/listinfo/fedora-devel-list
