When a computer starts running extremely slow and a simple restart fixes it, what is really happening?

Question

When a computer starts running extremely slow and a simple restart fixes it, what is really happening?

In: 216

Answer 1

My best analogy is your computer is like your kitchen. In an ideal world, you do one task in the kitchen, clean up and the kitchen is returned to its ideal state: clean, organized, ready to do anything.

But as you cook, dirty dishes pile up in the sink. To wash the veg, you have to move the dirty dishes. Can’t put them in the oven, the lasagne is cooking, I know stack em on the sideboard. Crap, where do I put the lasagne to cool out of the oven, the sideboard is stacked with dirty dishes. Etc. As you do work, if you’re lucky, you clean up partially, but things become more disorganized and cluttered until all of the working space of your kitchen (if not elsewhere in your house) is occupied by stuff that needs to be cleaned, or stuff that is work in progress for something else, and the entire thing grinds to a halt and your order in Chinese food. In our cluttered kitchen, to do anything, even something simple, you have to do seven other things first. [Like Hal changing a lightbulb.](https://www.youtube.com/watch?v=AbSehcT19u0). Things get real slow.

In your computer, resources are finite, whether its open handles to access files on storage drives, memory, or process/threads in the CPU. Usually, if a program finishes, it cleans up after itself. But sometimes it doesn’t. Sometimes you launch one program and it actually spins off a bunch of copies of smaller helper programs or sub-programs to do stuff, and sometimes these never get cleaned up. Sometimes programs write large files of interim data and never get deleted. Sometimes a program gets stuck waiting on something to happen that never does (like you’re waiting on the 10 yr old to take out the garbage but they never do) and so its frozen. Eventually your computer gets clogged just like in our kitchen analogy.

Rebooting a computing device.. any operating system really.. is like cleaning your kitchen: everything returns to a good, known, base clean and organized state.