Hi, folks,

I have 2 PCs running BOINC currently, one with an AMD dual-core 64-bit CPU, the other with a single-core Pentium 4 32-bit CPU. For some time now, both machines indicate they have 2 CPUs.

The older Pentium 4 PC shows this line in the BOINC log:

"8/16/2006 10:23:41 AM||Processor: 2 GenuineIntel Intel(R) Pentium(R) 4 CPU 2.60GHz"

I've tried resetting the Environment variable NUMBER_OF_PROCESSORS from 2 back to 1 (using Windows 2000 Pro), but it keeps getting reset back to 2.

Is BOINC the culprit, and if so, how do I fix this?

I think it is interfering with reasonable scheduling of work on the W2K PC, because it seems to be overcommitted frequently.

Thanks!

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Andy Barnett
USA

Which BOINC version is this?

Windows 2000 doesn't do Hyperthreading, the Operating system was released before this option was available. Yet if you have recently reinstalled, with SP4 included in the install, it is possible that Windows installed itself with the multiple CPU option that it has. You can check through this MSKB article if that's the case. Just check if you have a Uniprocessor or a Multiprocessor! Don't change anything!

Else disable Hyperthreading in your computer's BIOS.
Or set BOINC for the project you are crunching to use 1 CPU. You can do that through Your Account, General Preferences, change the option On multiprocessors, use at most to 1 processor, save the changes to the preferences page, and then update that project through BOINC (Open Boinc Manager, Projects tab, select the project, hit Update).

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Hi, Jord,

I am using BOINC 5.2.13 according to the About BOINC. The PC has Windows 2000 Pro with Service Pack 4, 1GB RAM, and the Control Panel / System / Device Manager / Computer indicates ACPI Multiprocessor PC, and the Advanced / Environment Variables / System Variables / NUMBER_OF_PROCESSORS is 2.

Before I had the AMD Athlon 64 x2 PC (running Windows XP Pro x64), I was using a much older dual processor Pentium II 400 MHz system with XP Pro. That system was when I first set the BOINC maximum processors to use at most 2 processors, and I believe it was sometime after that the W2K PC started listing 2 processors on the BOINC logs. But I really am not certain. It may have said so all along, and I never noticed, because really the only thing that seems to be affected is that BOINC on W2K seems to get overcommitted, and will say it running two tasks even though there is only one core CPU.

Is there a way I can set the max CPUs on BOINC to 1 for the W2K PC, and keep it at 2 for the AMD PC?

Thanks for your help!

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Andy Barnett
USA

Hi, Jord,

I am using BOINC 5.2.13 according to the About BOINC. The PC has Windows 2000 Pro with Service Pack 4, 1GB RAM, and the Control Panel / System / Device Manager / Computer indicates ACPI Multiprocessor PC, and the Advanced / Environment Variables / System Variables / NUMBER_OF_PROCESSORS is 2.

Before I had the AMD Athlon 64 x2 PC (running Windows XP Pro x64), I was using a much older dual processor Pentium II 400 MHz system with XP Pro. That system was when I first set the BOINC maximum processors to use at most 2 processors, and I believe it was sometime after that the W2K PC started listing 2 processors on the BOINC logs. But I really am not certain. It may have said so all along, and I never noticed, because really the only thing that seems to be affected is that BOINC on W2K seems to get overcommitted, and will say it running two tasks even though there is only one core CPU.

Is there a way I can set the max CPUs on BOINC to 1 for the W2K PC, and keep it at 2 for the AMD PC?

Thanks for your help!

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Andy Barnett
USA

You can set up a venue for either of the two PCs. All projects allow 4 venues so far, the default, home, work and school. If you set up the Windows PC to run in its own venue, then you can change the preferences for that PC separately from the other.

If you want specific help on that, say which project it is for and I'll write something up for you to follow.

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Thanks, Jord,

I'll give that a try!

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Andy Barnett
USA

Hi, Jord,

That did the trick - thanks again!

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Andy Barnett
USA

I know your problem is fixed already, but I did ask around a little, as my first post here was more based on a hunch than on actual fact. :-)

But it's true. Since Win2k can't support Hyperthreading, your one CPU is seen as two and handled as two. It's impossible to disable Windows 2000's support for that without reinstalling Windows and using the ACPI Uniprocessor option.

It is possible to set Windows 2000 from a Uniprocessor to Multiprocessor, when you install two or more CPUs (if your motherboard is capable of doing so), by using the link I gave above. But back ins't possible without a reinstall of the OS.

Do know that the Hyperthreading CPU is seen as two independent CPUs by Windows 2000. Windows XP does support HT, Win2k does not.

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On a Xeon board I have a BIOS option to disable HT, Win2k server can see two CPUs then, whereas it reports 4 with HT.

The counter reported by BOINC is the maximum number of BOINC tasks it can do concurrently, not really the CPU count. A quad core HT CPU will report 8 CPUs (and most likely need more than one project to fill the cache), even if all the stuff is on just one chip.

Often allowing 2 BOINC tasks on a HT CPU, the overall throughput is better than with HT disabled, so if BOINC "thinks" that there are 2 CPUs, just let it use them. Especially if you run a mix of projects, it is an advantage.

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Thanks folks!

I had a spare XP Pro license, so I installed it to help out with the HT part, and it of course still lists NUMBER_OF_PROCESSORS=2, and runs two tasks at a time.

But as you say, this is probably better than forcing it to run just one task, so I'll just let it be.

Thanks so much for your help everybody!

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Andy Barnett
USA