Windows XP 64-Bit Customer Preview Program

MBCook writes "I just notice that Microsoft has a new Windows XP 64-Bit Customer Preview Program starting today (February 3rd). If you have a AMD Opteron or Athlon64, you can go to the download page to get your copy. It's a pre-release copy that will expire in 360 days (which probably means the final will be out by then). Now Intel just changed their 64-bit plans, and all of a sudden this appears. Speculate away!"

Comments

Actual Performance Difference

[neomage86]

I wonder if a 64 bit OS will make any performance difference for the average desktop user. Since its not like any normal people have more than a gig of ram anyways. Is it possible that it could even slow down 32 bit apps?

Re:Actual Performance Difference

[Zeinfeld]

I wonder if a 64 bit OS will make any performance difference for the average desktop user. Since its not like any normal people have more than a gig of ram anyways. Is it possible that it could even slow down 32 bit apps?

Its been a long time since I had performance issues due to CPU bottlenecks. My twin processor 650MHz box works just as fast as my 2.4GHz single processor box in practice.

The big issue for me are the cases where the stupid machine just locks up and does fuck all for 20 seconds or so. CPU meter shows 3% utilization, no disk activity. What is the stupid thing doing?

Same goes for UNIX systems, its not the processing thats the issues, or even the legitimate I/O delays, its the cretinous delays built into broken device drivers and applications.

I would like Windows to have a meter built in that would show which processes were waiting and the resources they were waiting on.

My other pet peeve is what the cretins at Checkpoint think is an acceptable VPN client. Every time the credentials time out a box appears for me to re-enter my credentials. Only I use cert based credentials stored in CAPI so all I am doing is hitting OK. Even so the box locks the user interface for about 90 seconds while it does something. Oh @$#(& it did it again.

Re:Actual Performance Difference

[Miguelito]

Well I did some benchmarks using openssl's built in speed tests, and running in 64 bit vs 32 bit made a HUGE difference. Of course that was running a 64bit openssl as well. The opterons I have access to even beat the Itanium2s I have access to at work. By a lot in the smaller bit key sizes, but still either tied or beat the ia64 in the larger key sizes.

Here are the charts I made in OpenOffice on the data I collected. Even a 2GHz opteron beat a 3.2Ghz Xeon in 32 bit mode. :)

Of course this was just a benchmark, but it does show that things that use openssl would benefit from running under 64bit on an opteron.

Re:Actual Performance Difference

[Soko]

NT for Alpha had no long pointers and the same 4GB memory limit etc. as its IA32 counterpart. The processor was certainly 64 bits, but the OS was 32 bits at it's core. IIRC there were some places where they had to use 64 in order to get the thing to load, but not where it counted.

If Microsoft had actually used the Alpha to it's fullest potential, all of my servers would likely be runnning 21464s, not Xeons.

Yes, I'm still mad at DEC/Compaq/HP for squandering the Alpha tech. *grumble*

Soko

Intel will have to follow AMD

[Random BedHead Ed]

At this point there's enough Opteron stuff out there that Intel can't avoid implementing an architecture compatible with amd64. Yes, I think the timing is probably not a coincidence. Though I'm sure Microsoft wasn't waiting for Intel, they probably informed Groves and Co. of the release in advance.

If Intel can't stay compatible with AMD's lineup they could end up behind. That would certainly be a first for Intel.

Intel is not impressing me these days

[AviLazar]

I still recall reading the article in Wired magazine a few months back. A company approached them with an offer to provide them perfect diamond wafers (produced at less then $5/wafer) and Intel did not take the offer because they have not gotten their full investment back on the silicon. So given that they refused to have an easy method of increasing their processor spead by a very big number, it is not surprising that they still haven't gotten 64 bit over AMD... Shame, Intel used to be the best. -A

Re:Windows Media Player?

[ikewillis]

Evidently you haven't heard about the Windows-on-Windows (WoW) subsystem utilized on AMD64 processors:

"The Microsoft(R) WOW64 (Windows(R) on Windows) subsystem will allow most 32-bit applications to launch seamlessly on 64-bit Windows," said Brian Marr, Windows product manager. "WOW64 is designed to provide interoperability and great performance on AMD64 processors across the 32/64-bit boundaries. As customers migrate to 64-bit Windows XP and Windows Server, they will have a code base that will support both 32- and 64-bit applications."

While it's wonderful Linux understands multiple ABIs natively, Windows does not, and utilizes WoW to seamlessly launch 32-bit applications on 64-bit builds of Windows.

sizeof (long long) == 8...

[Ayanami Rei]

and the Opteron can hold it one register. Just prefix the instruction with the OTHER size prefix byte. (for those who don't already know, most intel instructions if operating on a 16-bit short require a prefix byte. On the Opteron, you use a different prefix to get 64-bit ints and the extended regs)

There are plenty of places where it makes sense to use 64-bit regs, especially in the kernel when involving counters, timers, GIDs, and such.