Anyway, the process that was taking so much CPU was Windows Explorer. I'm pretty sure that is a Microsoft problem, especially since the computer just was booted up.
Funny how you assume that my Windows system is not configured to my usage.
I've turned off Windows Defender. I've turned off background tasks that I don't want. I've uninstalled every piece of software I don't want. I've turned privacy up as high as I can.
I use HDD's on purpose. If Windows cannot use HDD's, that is bad programming. That's just how it is. Microsoft should not assume that HDD's don't exist.
I use an HDD on Windows for two reasons: one, I am cheap, and two, I am writing a VCS. The Git experience on Windows is already terrible, so I'm setting myself up to have a worse experience on Windows than any of my users. Why? Because if it's painful enough, I'll fix it. This is the same reason I use HDD on Linux: to ensure that my code is as fast as possible for users.
I have disabled Windows Update and other background maintenance tasks. Don't assume I haven't.
If you really purport yourself as good enough to give advice to a programmer, please at least don't assume stuff about that programmer and his environment before going on a pointless tirade that did make you seem like a jerk.
By the way, I scanned my Windows drive with various tools. No errors, and the lifetime number of hours, which I was hinting at with my glib reference to its age and how much space is taken, is only a fraction (1/5) of the average lifetime of drives like this.
> That's not always an option -- my last android phone died with a reboot loop.
You're not wrong, but for future reference, there is a way to stop such a reboot loop; I did it just yesterday with my wife's phone. (Of course, it was a Pixel, so it might not be on every phone.) You do it by holding power and down volume until it says "Command not found", then you hold power and volume up until you get a menu. One of the items should be "Power off". Another one is "Factory reset" or something like it.
Once my wife's phone was off, I left it off for a couple of hours to let it cool. Then I booted it again, and all was well.
The hang on shutdown turned out to be because I kept a USB thumb drive plugged in.