Memory, and why the computer slows down
Exactly what is happening when a machine grinds to a halt with too much open — and what to do about it in the next thirty seconds.
Memory — nearly always called RAM — is the space the computer works on. Everything you have open at this moment is sitting in it.
A counter twice the size does not make you a faster cook. It lets you have more on the go before you have to start putting things away to make room. That is exactly what memory does, and exactly the difference it makes.
When memory fills, the computer does not stop. It picks something you have not touched for a while, writes it out to the storage disk, and uses the space that frees up. When you click back to that window, it has to go and fetch it again.
Storage is thousands of times slower to reach than memory. So the machine carries on working, but every switch between windows now involves a trip to the filing cabinet. That is the treacle, and it has a name: swapping.
Key points
- Memory holds what is open right now, and empties when the power goes off
- When it fills, the computer shuffles things out to the disk — and that shuffling is the slowness
- Closing something or restarting fixes it immediately and costs nothing
- More memory is often under $40 on a desktop or an older laptop
What to remember
- The moment it turned treacly is the moment the computer ran out of counter and began shuffling things out to the disk to cope. That shuffling is the slowness.
- Slow when full, fine when empty, fine again after a restart. That is memory, every single time.
- Only three things add counter: closing something, restarting, or fitting more memory. Everything else on that list is solving a different problem.
Try this
Open Task Manager on Windows (Ctrl+Shift+Esc) or Activity Monitor on a Mac, and watch the Memory figure while you open and close a few things. Seeing the number move is the fastest way to make this stick for good.
Practice: Memory, and why the computer slows down. Your first lesson is free, with no account or card; the rest are part of a Lantern plan. Interactive lessons require JavaScript.