FC5T2 and Development issues, observations, and questions

[Dave Jones]

On Tue, Jan 17, 2006 at 08:09:18PM +0100, Thorsten Leemhuis wrote:
 > > >  I disagree, I suspect there are still a lot more non-dual/ht systems 
 > > > out there. I just upgraded to dual core A64. They come at quite a 
 > > > premium. It also isn't like a ton of S754 systems and S939 single core 
 > > > systems haven't been sold. I will give you that there are a fair number 
 > > > of HT systems out there, but again they are only on the higher end 
 > > > versions of the processor. In addition may people disable HT worse 
 > > > performance under certain workloads.
 > > The spinlock operations are almost free on AMD on UP.  They did some real
 > > magic in their cores to make locked operations really fast compared to Netburst.
 > > Intel however haven't shipped *any* UP x86-64's. Even the first ones
 > > they shipped were HT capable.
 > 
 > Sorry, but I have to disagree: Most newer Celerons have x86-64 these
 > days, too (since June or July iirc). And those are UP/have no HT... See
 > http://www.intel.com/products/processor/celeron_D/index.htm

Excellent point. These are probably going to see the most benefit from the
LOCK->NOP runtime conversion when that goes in, though the vast majority
of users will never notice any difference.

		Dave