At some point, you’ve had a tech problem. Maybe you’ve asked a friend, or maybe you’ve called or chatted with someone. What’s their first suggestion? It’s always to reboot the equipment. Turn it off, unplug it, leave it for 30 seconds, and start over. The thing is, you may grumble about taking this step, but it works more often than you’d think. But why? There are several reasons why a reboot makes sense. You may not ever know which reason solved your problem, and that’s probably ok as long as one of them does.
Sometimes something has frozen up
Even the simplest device generally has dozens of programs running at the same time. Decades ago, every device was designed with its own custom-written computer code. Since processors are so cheap now, a lot of devices use general-purpose code that’s just been customized for a particular application. It shouldn’t surprise you to hear that any “smart” device in your home probably runs Linux or some other embedded operating system. Whenever an operating system is used, there are hundreds or thousands of modules that run at the same time. They run over and over, and sometimes, something random happens. With so much going on, it’s a wonder these things are as reliable as they are.
When you reboot, it closes all these routines and starts them up again. Sometimes that’s all it takes.
Sometimes a log is full
This is another thing that happens with smart devices. It’s very common for devices to save little bits of information in a log. This log is used during the development process to make sure that everything is running properly. It’s common practice to leave that log running even when the device is in its final form. Programmers don’t want to change anything once they know it works, even if it’s something very small.
These logs are checked and often cleared every time you reboot. However, if you haven’t rebooted in a while, those logs can grow to such a size that they become a problem for the device to write to. This famously happened with older Teslas which required expensive upgrades because their logs got too full after years of driving. It wasn’t really possible to test that ahead of time.
When you reboot, your device will generally clear a lot of smaller logs which may make things run more smoothly.
Sometimes just going through the startup checklist fixes things
There are all sorts of tasks that your device only does once per reboot. Some include checking its storage to make sure it isn’t corrupt or testing communications pathways. Desktop operating systems will tend to do some of these tasks if there hasn’t been a reboot in a while, but as you get to the simpler devices like smart home equipment or TV receivers, that process doesn’t happen as often. Those devices just don’t have enough processor power to spare in order to make it happen.
When you reboot, the device goes through a series of steps that are designed to make sure it’s in working order, and sometimes just doing that re-establishes the pathways that are needed. Sometimes a device can repair corrupted storage that is causing problems as well.
While we’re on the subject, why do you have to unplug things and wait before plugging them in?
Practically every modern device, even simple ones like kitchen appliances, has at least one capacitor in it. A capacitor is something similar to a battery. It temporarily stores current and lets it out in a consistent way. While a battery is designed to hold onto that current for a while, a capacitor isn’t. Its purpose is just to make sure that the current going out is at the right rate and is going through consistently. Consistent current is important for anything that uses timing, in other words anything with a computer chip.
Have you ever unplugged something and its power light stays on for a few seconds after you unplug it? That’s due to the capacitor draining. That capacitor is still supplying some power even though it’s not getting any from the wall. That’s how it’s supposed to work.
Generally, most capacitors drain by at least 95% in about 5 seconds. However, it can take up to a minute to drain a capacitor to that level. If a capacitor is still supplying current, the computer chips inside the device can still be functioning at some level. That means they may not completely reset their states when you plug the thing back in.
Giving those capacitors time to drain means that when the device starts up again, it begins from “ground zero” and that means the best chance of making sure everything works again.
