Disable CPU cores in Linux

WARNING: You should close all applications before you execute these commands, because otherwise your system might lock-up.

WARNING: Please close all applications before continuing.

You can conserve energy, reduce heat, and very indirectly lengthen your computer's longevity, by turning off some CPU cores.

For example:

To turn off CPU #3:

echo 0 | sudo tee /sys/devices/system/cpu/cpu3/online

To turn off CPU #4:

echo 0 | sudo tee /sys/devices/system/cpu/cpu4/online

To turn off CPU #5:

echo 0 | sudo tee /sys/devices/system/cpu/cpu5/online

And, et cetera.

To turn on CPU #3:

echo 1 | sudo tee /sys/devices/system/cpu/cpu3/online

To turn on CPU #4:

echo 1 | sudo tee /sys/devices/system/cpu/cpu4/online

And, et cetera.