Dual CPU woes
I have a hyperthreaded, dual processor Intel Xeon workstation, under my desk at work, that runs Windows 2000 Professional (don’t ask; company prescription). I need the beast to perform some specific tasks. I have been trying hard to stretch its guts to its threshold limits — use all its raw power, without luck.
The OS refuses to show dual processors in the hardware profile and in My computer. I am confused. Either the machine is actually being stretched to its limits and still can’t handle the stuff I am throwing at it, or it is being under-utilized (Is it the OS version?). Either way, I am seeing core dumps of my monstrous 200,000 element strong finite model.
Does anyone know how I can make sure that I am getting the best out of it?
Update: Oh my goodness, DEP (a default setting in any well patched Windows system) was the reason why Abaqus was core-dumping my model’s stiffness matrix mid way, and puking out python error codes. Following error gave me a clue about what was happening:
"***ERROR: Issue cannot be deleted Not all data Released"
Although, a search on the topic (on Abaqus support site) only showed that this setting was synonymous with XP and 2003, I realized that it could also be applicable to 2000. This was one of the lesser known (and generally considered good) features that was brought forward from 2000 into XP and newer versions.
Solution to the problem was simple enough, according to this KB article and I changed the boot.ini file (in root) to append the first line under [operating systems] with this:
/noexecute=AlwaysOff
But as this KB says:
This setting does not provide any DEP coverage for any part of the system, regardless of hardware DEP support. The processor does not run in PAE mode unless the /PAE option is present in the Boot.ini file.
Ideally I would prefer it to be:
/noexecute=OptOut
DEP is enabled by default for all processes. You can manually create a list of specific programs that do not have DEP applied by using the System dialog box in Control Panel. Information technology (IT) professionals can use the Application Compatibility Toolkit to “opt-out” one or more programs from DEP protection. System compatibility fixes, or shims, for DEP do take effect.
But there’s no example of how I could create an opt-out for a specific program like Abaqus. That would be helpful, especially in Windows 2000 (as its System Properties menu differs from newer Windows versions and there’s no easy way to do this).
My first thought was to recommend you talking to your company’s IT people. And still is my first recommendation.
Is the application you are running multiple processors aware? Is the BIOS “seeing” the two processors? How much RAM do you have? How much VRAM?
Either way, ask your IT folks. THey should have the answer –and fix, if any– that you look.
Feb 26, 07 at 20:42There are multiple things -
1.
2.
Feb 27, 07 at 04:50Also look up @ http://en.wikipedia.org/wiki/Dual_core in software impact section to understand why software itself needs to be re-written to take advantage of the multiple cores. It is an active research area in more # of cores/interaction of caches/memory levels and change in programming itself.
Following are few easy to grok language attempts
Feb 27, 07 at 06:26David, Govind, thanks for the tips. I will have to go through the IT folks once more. But here’s what I see.
The application supports it; and I have CDs for all flavors. I have the x32 version installed, just to be on the safer side.
The workstation is HP xw8200 (pdf link). The BIOS shows two CPUs but is assigned to the same CPU ID. 4GB RAM in BIOS, but the OS shows only 3GB. 2 x 256MB VRAM — two graphic cards.
I could, as you suggested, run once more to the IT folks, but I am not expecting anything more than what I already have. A classic case of WYSIWYG, and the change/upgrade of OS is not negotiable. So part policy, part hardware problems, if you like.
Tomorrow, I am running with some folks who use this on a daily basis to get some insights on how they use it. If I have enough reasons, I might ask out IT to reconsider the OS.
Govind, I will be digging those links in the meanwhile, thanks a ton!
Feb 27, 07 at 09:28Ok, to make the OS to see all the memory, follow the instructions at this wiki page, since I am afraid your OS is not “seeing” all available memory.
Some applications designed for 2 processors will work badly if you have only one *with* hypertreading. Try disabling hypertreading and see how it goes.
Feb 27, 07 at 16:30PAE - ability to see large memory was added to os when intel chips supported it. It is available by default in Win2k3 kb article It was challenge with 32 bit machines and OS combined with chip’s ability. My suggestion in this case is also to take help of the vendor for this. Technically for your kind of workload you should use the 64 bit machine - becuase most of these apps require access to that kind of memory by default and data sets are massive as in your case.
Feb 28, 07 at 10:33In your case this more of hyperthreading(HT), try disabling that.
Just one clarification - when you say you say only 3 gb for os? what do you mean? where do you see this?
Both are identical processors. I tried with AIDA32 (a decent tool to check what’s under the hood). No luck. Here’s how the menu in ABAQUS looks like:
Feb 28, 07 at 15:49hello chethan
good to see your website. you write well. i tried to respond to your malaysia post, but unfortunately it was closed for sometime now.
i stayed in KL for a year b/w 2002-3 in Damansara, PJ.
do put a mail across to me and I ll write more. nice knowing you.
Blogging is an art, and you are good at it. Was particularly reading about your bangalore airport entries.
Srikanth.
Feb 28, 07 at 16:45I think I might have been unclear in my post about this: I see 3GB RAM as Windows reads it: My Computer > System Properties > General (tab)
Whereas, the BIOS reads 4GB.
Feb 28, 07 at 16:52good to know.
Mar 7, 07 at 05:18