OSDev.org

This is probably a stupid question but here it goes. If I have a computer with multiple cores, how do I tell the computer which core to use for different instructions? Or does the computer take care of all this (I guess i can affect it, if I want to run two threads on two different cores). Suppose I create a small OS, as Im currently doing. Do I have to care about the double cores or will it work anyway (I've only tried it in Bochs).

The "main" core (called the BSP) boots like normal. All the other cores (called the APs) are basically HLT'ed, until you send them a special interrupt. You have to do a whole lot of work to get the APs to do much at all. To get them to run programs, you need to write a scheduler that chooses which AP to run a process on, and then directs that AP to run the code at a specific memory address.

Thanks! Using multiple cores isn't something I care for right now, just wanted to make sure that a OS that's written for one core still works