Jim Kloss of the late Whole Wheat Radio, nochange BBS, Xchange file transfer application, and all around wonderful person tweeted this in response to my irrational computing post:

In the olden days I habitually ran defrags. Often several per day. Irrational because never got a noticeable performance gain. Embarrassing because I sat hypnotized and watched blocks being moved around for 3, 10, maybe 20+ minutes.

One of the first programs I ever bought with my own money was Diskeeper, to run on my DIY Windows 2000 tower. I could have used the built-in tool—which I later learned was based off Diskeeper—but its visualisations were even better. And like Jim, I was under the misguided notion that it made a huge difference in performance. Either way, SSDs saved us from so many things in our workstations and laptops, not least fragmentation!

He continues:

These days, my most irrational action is to constantly close things not being used. Even if I know I’ll open them 20 minutes later. Better to close and re-open than to eat up a massive 3K’s worth of 5GB memory!

Also this! I see people’s macOS docks and Windows taskbars and I blanch. Even if I weren’t concerned about memory usage, I feel like cognitively there’s more overhead having too many things open to track. Right now on my Mac I have Firefox, Emacs, the Terminal, KeePassXC, our company’s self-hosted chat client, and Outlook; that’s it. My FreeBSD tower is about the same. And even that lists already feels like too much.

It’s a bit tricker now because awful, Electron-based software bundles entire web browser frameworks into applications that just deal with text. In that case, closing a simple program can have a breathtaking effect on resource use.