CPU scheduling and the effect of multiple vCPU VMs

Modern CPUs are so powerful that we perceive the ability to multitask or use several programs at once. In reality, CPU cores act in a very serial fashion, that is to say, a single core is only ever really executing one task at a time. Because of the speed and logic in these modern processors, they are able to quickly switch between the requests from different applications, so when one request is finished, the CPU switches to the next task and so on.

A technology such as Hyper-Threading (HT) by Intel or AMD-V/RVI will make a single core appear as two cores to the operating system and can help process multiple requests at once on a single CPU core.

If you have HT enabled, you will see that your OS, ...

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