Programatically detect number of physical processors/cores or if hyper-threading is active on Window

Posted by HTASSCPP on Stack Overflow See other posts from Stack Overflow or by HTASSCPP
Published on 2010-05-25T02:57:07Z Indexed on 2010/05/25 3:01 UTC
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Filed under:

c++

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Windows

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mac

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assembly

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hyperthreading

I have a multithreaded c++ application that runs on Windows, Mac and a few Linux flavours. To make a long story short: Inorder for it to run at maximum efficiency I have to be able to instantiate a single thread per physical processor/core. Creating more threads than there are physical processors/cores degrades the performance of my program considerably. I can already correctly detect the number of logical processors/cores correctly on all three of these platforms. To be able to detect the number of physical processors/cores correctly I'll have to detect if hyper-treading is supported AND active. My question therefore is if there is a way to detect whether hyperthreading is supported AND ENABLED? If so, how exactly.

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