Apparently, there’s some coordination mechanism, where you tell the OS that you want to remove a certain memory stick, so it moves all the memory onto other RAM sticks (or uses paging to move it to your hard drive). Only then would you actually physically unplug the memory stick.
I guess, you could see it that way…? The important part is that you don’t have to turn off the whole system. It can continue running without interruption. So, the RAM will be lukewarm when you swap it, but the system will still be hot.
Apparently, there’s some coordination mechanism, where you tell the OS that you want to remove a certain memory stick, so it moves all the memory onto other RAM sticks (or uses paging to move it to your hard drive). Only then would you actually physically unplug the memory stick.
See, for example: https://docs.kernel.org/admin-guide/mm/memory-hotplug.html
(Mind that this is kernel documentation. If you actually want to do this, there’s probably some CLI program to make it easier.)
Then it’s not Hot Swap, just Lukewarm Swap?
I guess, you could see it that way…? The important part is that you don’t have to turn off the whole system. It can continue running without interruption. So, the RAM will be lukewarm when you swap it, but the system will still be hot.
If you really want to be pedantic you could setup raid 1+0 or 5 and live the true RAM hot swapping life
So “warm plugging” is a thing - it means a piece of hardware is detachable while the machine is asleep.