Replies to post #3341 on Advanced Micro Devices Inc (AMD)

[dougSF30]

wbmw, Re: Re: 2-5

2. Sure Microsoft does. They want to sell software. Including 64-bit versions of Windows. Intel is telling people there's no large need for 64-bit (for the consumer) until 2007. AMD is shipping Athlon64 in September. If you're Microsoft, supporting AMD64 makes great sense.

3. Let's agree: Itanium dissipates "significantly more" power than Opteron.

5. I'm not sure about that. I expect the AMD64 beta of Windows 2003 Server due this summer will include the .NET framework.

I very much disagree on the Yamhill impact. Even one tiny hint of another 64-bit product from Intel will put Itanium purchase decisions on hold, if not outright kill them. No one wants to buy a soon-to-be-discontinued product, and that will be the perception. And that perception will make it the reality.

Doug

[yourbankruptcy]

wbmw. 2. Optimisation costs much less than the port and validation. 20% of the code is executed 80% of time. Microsoft just has to assign best engineers to those 20%.

Why they need that? In server market it is important to command the top in benchmark lists. Even if he customer will end-up buying the Xeon server instead of Opteron, he must see that his faworite benchmark is running great with Microsoft. Or he will start thinking about Linux, because all Linux-based products will be optimised very soon.

[spokeshave]

wbmw: Re: I wouldn't presume it scales linearly with frequency.

Unless there has been a change in the laws of physics, this is incorrect. All else being equal, power dissipation scales roughly linearly with frequency. There are minor modification factors that are non-linear, but in every model of power dissipation I have seen it looks something like this:

Power = {(stuff)x(frequency)}/(more stuff) + stuff

Where in general, "stuff" is constants such as voltage and scaling factors. "More stuff" can be slightly non-linear, but for the most part, there is a practical direct proportional relationship between power and frequency.

This is elementary physics.

[jhalada]

wbmw,

2. Microsoft has no reason to invest in Opteron optimizations. That was the original subject for #2, was it not? It sounds like their support will be minimal, and highly leveraged off of the work they already did for Intel.

I think you are mixing 2 subjects: SpecInt optimization and general optimization to perform well on current hardware.
Microsoft has no reason to invest in SpecInt optimizations, but I expect a competent C++ compiler and .NET Opteron engine. Microsoft wants to sell software, and has interest in Microsoft software performing well against the competition. Microsoft software is compiled using Microsoft compilers.

Microsoft has already done some of work on Opteron optimizations by working on 64 bit Opteron compiler and by taking advantage of the extra registers.

5. Windows 2003 Server is missing the .NET framework for Itanium 2. This is unfortunate, but not a barrier for entry right now.

If you are considering running any .NET code on the server (ASP.NET, ADO.NET or custom apps) it is an insurmountable barrier for entry.

Itanium's competitors will not be using .NET, and it's doubtful that Microsoft will get a 64-bit version for Opteron before Itanium.

Opteron can run .NET as is. 64-bit version will be an icing on the cake.

Joe