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Is there a way that I could emulate the number of logical/physical processors for Windows like virtualization (VM) ?

I need to simulate processors of about more than 64 and see some minor functionality of some C++ calls in Windows Server 2008 R2

Edit: I just need the system to tell that it has more cores, performance and accuracy is of no concern

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Can you be more precise about what you want? Do you want to see the system tell you it has more processors? Or do you want the system to execute code the way it would if it had more processors? Do you need accuracy? Do you need performance? – David Schwartz Jun 4 '12 at 11:18
well actually my reason might be stupid/longshot but i wanted to check this out… – Basit Anwer Jun 4 '12 at 11:21
Related on Serverfault. – Diogo Jun 4 '12 at 12:50
I've experimented with VirtualBox, QEMU, KVM and OpenVZ. Whenever I selected more cores that the server actually had available (Including HTT), the virtual machines would come to a crawl. They did not like being 'fooled' that there were 64 Processors available when in fact there were only 32. – kobaltz Jun 4 '12 at 19:28
meaning that a virtual OS can be fooled in thinking that it can have a more CPUs than physically available – Basit Anwer Jun 5 '12 at 5:44
up vote 5 down vote accepted

Yes, there is a way, actually there is also a open-source processor emulator called QEMU, you can use it with the -smp X argument:

QEMU is a generic and open source machine emulator and virtualizer.

When used as a machine emulator, QEMU can run OSes and programs made for one machine (e.g. an ARM board) on a different machine (e.g. your own PC). By using dynamic translation, it achieves very good performance.

When used as a virtualizer, QEMU achieves near native performances by executing the guest code directly on the host CPU. QEMU supports virtualization when executing under the Xen hypervisor or using the KVM kernel module in Linux. When using KVM, QEMU can virtualize x86, server and embedded PowerPC, and S390 guests.

Also, if you want to know more about core emulation, read this article on section 2 - "the CPU Emulation Core" or even on this post on ServerFault.

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Ahh yes, cause QEMU actually virtualises the entire CPU instead of doing passthrough. You lose out on performance, but its a LOT more flexible. – Journeyman Geek Jun 6 '12 at 12:08
Good descriptive answer. Thankyou :) – Basit Anwer Jun 7 '12 at 5:30

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