News: Conroe doesn`t gain advantage in 64bit environment

[Cooper]

According to the internal document from the manufacturers (Intel Extreme 2 X6800 vs Core AMD Athlon 64 FX 62 & Intel Pentium XE 965) Pentium XE 965 could perform 5-10% (2-3% for Athlon 64 FX 62) explains in 64-bit, Core 2 center was found no obvious boost.

Source

[Mr. Popo]

[RPGWiZaRD]

Wonder how long Intel can/is going to ditch 64bit, sooner or later they will have to jump on the bandwagon.

[aMp]

I thought that moment would come with Vista, but now I'm not so sure. Anybody got a link explaining which 32-bit apps will work/have problems with Vista, and why?

[TEDY]

CONROE is 64bit cappable right?

[514y3r]

CONROE is 64bit cappable right?

Yup... Has Intel's EM64T.

[Richteralan]

These are Intel's numbers.
For real environment these numbers will be more

[Ailleur]

How about "cpus dont gain from 64bits" for a more accurate title (in regards to the article posted)

[uOpt]

How about "cpus dont gain from 64bits" for a more accurate title (in regards to the article posted)

The point here is that Core2 gains less from running 64 bit code than AMD64 does, at least that is what some people said.

I am running a benchmark on this as we speak, eta 20 minutes.

[Ailleur]

The point here is that Core2 gains less from running 64 bit code than AMD64 does, at least that is what some people said.

I am running a benchmark on this as we speak, eta 20 minutes.

Ahh yes my bad, when i first read the sentence i thought every intel scored 5-10% higher and all of amd was 2-3%.
Carry on!

[ScottFern]

Source

Yeah I don't think so.

[Cooper]

Yeah I don't think so.

What`s wrong with the source ?

[onewingedangel]

So conroe performs close to its potential in both 32 bit and 64 bit environments and people complain, shouldn't the complaint be that amd's performance drops so much from moving from the native 64bit to 32bit mode?

Conroe outperforming amd in both 32 and 64 bit environments certainly removes another factor from the performance showdown however.

[ozzimark]

So conroe performs close to its potential in both 32 bit and 64 bit environments and people complain, shouldn't the complaint be that amd's performance drops so much from moving from the native 64bit to 32bit mode?

K8 is 32bit and 64bit native. it's not that there is a drop from 64bit to 32bit, it's that the advantages of x86-64 give a performance boost when properly taken advantage of

[K404]

K8 is 32bit and 64bit native. it's not that there is a drop from 64bit to 32bit, it's that the advantages of x86-64 give a performance boost when properly taken advantage of

Still a shame about the drivers Maybe i`m out of date, but do ALL drivers still need to be 64-bit for Windows 64?

[uOpt]

I ran some 64 bit benchmarks in addition to my 32bit benchmarks.

In my 32 bit FreeBSD tests for C/C++ compilation a 2.40 Conroe with DDR533 is 5-8% faster than a 2.60 with DDR432 (*), or about 14-17% faster per MHz.

Running some similar C/C++ compilations on 64 bit Linux (all software 64 bit), the 2.40 GHz Conroe is 18-25% faster than a 2450 MHz Opteron.

I'd say the lack of 64 bit performance on Conroe is a myth.

This is preliminary. I have problems controlling the Conroe's clocks from Linux, I am not 100% sure I am actually at 2.4 GHz here. Damn BadAxe...

(*) Before anybody cries foul: the 5-8% of the 2.4 Conroe versus 2.6 Opteron are only for C/C++ compilation, Conroe goes to 20% advantage for scripting languages and Lisp and to 25-30% for low quality video. The number here are purely for C/C++ compilation. I full 64 bit version of my benchmarks is in the works.

[p360stick]

interesting

[nn_step]

(*) Before anybody cries foul: the 5-8% of the 2.4 Conroe versus 2.6 Opteron are only for C/C++ compilation, Conroe goes to 20% advantage for scripting languages and Lisp and to 25-30% for low quality video. The number here are purely for C/C++ compilation. I full 64 bit version of my benchmarks is in the works.

Would you mind running more tests for us?

[uOpt]

The full set of 32 bit results is here. Has the Conroe at a few frequencies and a ton of AMD64 chips and some Pentium-Ms thrown in:

http://www.cons.org/cracauer/crabench/core2.user.html

Results with multithreading/processes:
http://www.cons.org/cracauer/crabench/core2.wall.html

[nn_step]

Rather nice write up man.
Good work as usual

[ScottFern]

I ran some 64 bit benchmarks in addition to my 32bit benchmarks.

In my 32 bit FreeBSD tests for C/C++ compilation a 2.40 Conroe with DDR533 is 5-8% faster than a 2.60 with DDR432 (*), or about 14-17% faster per MHz.

Running some similar C/C++ compilations on 64 bit Linux (all software 64 bit), the 2.40 GHz Conroe is 18-25% faster than a 2450 MHz Opteron.

I'd say the lack of 64 bit performance on Conroe is a myth.

This is preliminary. I have problems controlling the Conroe's clocks from Linux, I am not 100% sure I am actually at 2.4 GHz here. Damn BadAxe...

(*) Before anybody cries foul: the 5-8% of the 2.4 Conroe versus 2.6 Opteron are only for C/C++ compilation, Conroe goes to 20% advantage for scripting languages and Lisp and to 25-30% for low quality video. The number here are purely for C/C++ compilation. I full 64 bit version of my benchmarks is in the works.

This is exactly what I was thinking about when I commented earlier. There is no way Conroe is somehow not optimized for 64bit Windows OSes. It seems more like propoganda than anything else.

[gazzoom]

uOpt
do these charts basically just support what u said in post #16? as I'm not familar with a number of those benchs, would you mind summarising the important impacts out of the result. thx

[Carfax]

If anything, Conroe should be superior to AMD in 64-bit due to using full SSE2 capabilities, which is very optimized in Conroe..

The performance might not be overly noticable at first, because most compilers were made with the K8 foremost in mind.

Intel's 64-bit compilers which will have Conroe optimizations should noticeably higher performance.

The type of application will vastly influence the performance gain aswell. Not every application will benefit from the use of expanded registers and SSE2.

[gOJDO]

What`s wrong with the source ?

There is no comparison, no evidence. Just thoughts. Also all Netburst, K8 and Core2 Duo will perform different on different OSes and different software in 32bit and in 64bit environment. For example the K8 perofrms almost same on WindowsXP x64 and many times slower than XP x32, but it performs much better on Linux 64bit than Linux 32bit. There is some explanation and it is reasonable, the instruction fetching. I wonder how Vista will be optimized for Conroe. Vista was cancelled many times and the last time was becouse Core2 optimizations.

[mibo]

I ran some 64 bit benchmarks in addition to my 32bit benchmarks.

In my 32 bit FreeBSD tests for C/C++ compilation a 2.40 Conroe with DDR533 is 5-8% faster than a 2.60 with DDR432 (*), or about 14-17% faster per MHz.

Running some similar C/C++ compilations on 64 bit Linux (all software 64 bit), the 2.40 GHz Conroe is 18-25% faster than a 2450 MHz Opteron.

I'd say the lack of 64 bit performance on Conroe is a myth.

This is preliminary. I have problems controlling the Conroe's clocks from Linux, I am not 100% sure I am actually at 2.4 GHz here. Damn BadAxe...

(*) Before anybody cries foul: the 5-8% of the 2.4 Conroe versus 2.6 Opteron are only for C/C++ compilation, Conroe goes to 20% advantage for scripting languages and Lisp and to 25-30% for low quality video. The number here are purely for C/C++ compilation. I full 64 bit version of my benchmarks is in the works.

Did I get it right?
You run compilation tests on a 32bit BSD kernel and a 64bit Linux kernel and compare the results.
I think even on one kernel there can be optimizations for one of the architectures present while the other runs unoptimized code (example: sse2 code for intel chip while no sse2/3dnow for amd). But with two completely different kernels this comparison is even more meaningless - I think.
If somebody can assure me that all the kernels are optimized for both architectures - but IMHO nobody can.

Just my 2cents
mibo