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CPU_CLK_UNHALTED.THREAD: multiple operating frequencies on one physical core?

AAhusk
Beginner
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The Software Developer's Manual mentions CPU_CLK_UNHALTED.THREAD and says

"The CPU_CLK_UNHALTED.THREAD event counts the number of core cycles while the logical processor is not in a halt state."

For CPU_CLK_UNHALTED.CORE, it says

"If there is only one logical processor in a processor core, CPU_CLK_UNHALTED.CORE counts the unhalted cycles of the processor core."

I'm confused because I've read multiple things saying that a physical core only has one operating frequency, i.e. cycles per unit time. But the CPU_CLK_UNHALTED.THREAD suggests that a logical core has it's own cycle count, and so two different logical cores, or threads, on the same physical core could have two different operating frequencies? Let me know where my understanding is wrong.

Where I read that a physical core only has one frequency(which I interpret as one cycle count as well):

Hyperthreaded cpus and their cores frequencies | Tom's Hardware Forum (tomshardware.com)

Hyperthreading CPU frequency question? | Tom's Hardware Forum (tomshardware.com)

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1 Solution
McCalpinJohn
Black Belt
409 Views

A physical core has only one clock, but this counter only counts when the corresponding  "logical processor" is not halted.  The two logical processors associated with a physical core can be halted independently of each other, so the accumulated counts for this performance counter event will generally be different.

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McCalpinJohn
Black Belt
410 Views

A physical core has only one clock, but this counter only counts when the corresponding  "logical processor" is not halted.  The two logical processors associated with a physical core can be halted independently of each other, so the accumulated counts for this performance counter event will generally be different.

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