RPM Optimization Changed in FC5

[George N. White III]

On Fri, 14 Apr 2006, David Cary Hart wrote:

> In FC4, the optimization string include mtune=pentium4. Does anyone
> know why this changed to mtune=generic? Is there a performance hit on
> P4s? Has this been documented anywhere? IIRC, developers claimed
> numerous performance benefits with the p4 tune.

The compilers/libraries have changed, as has the range of CPU's that may 
need to run fc5.  The average system running fc5 is faster than the 
average fc4 system, so it makes sense to compile with reduced optimization 
for reliability and simpler debugging.  It is quite possible that the code
that was causing poor performance with mtune=generic has been rewritten or
replaced.

What matters is whether your hardware performs acceptably with fc5. 
There are some apps (linear algebra, video encoding) that really must be 
compiled for the specific hardware configuration if you use them heavily.

-- 
George N. White III  <aa056 at chebucto.ns.ca>