alt Hacker News> macOS 15 uses ~5GB on startup without any app open
Sort of? Mac very aggressively caches things into RAM. It should be using all of your RAM on startup. That's why they've changed the Activity Monitor to say "memory pressure" instead of something like "memory usage."
I'm typing this on an 8 GB MacBook Air and it works just fine. I've got ChatGPT, VSCode, XCode, Blender, and PrusaSlicer minimized and I'm not feeling any lag. If I open any of them it'll take half a second or so as they're loaded from swap, but when they're not in the foreground they're not using up any memory.
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In macOS 15 there are two metrics: "Memory used" and "Cached Files"
I'm specifically talking about "Memory used" here.
In fact, on my 16GB mac, if I open apps that use ~8GB of RAM (on top of the 5GB I mentioned earlier), it starts swapping.
After several days of usage, Activity Monitor will usually shows that "WindowServer" is using 6 GB of RAM.
Yeah, 8 GB RAM does not cut it anymore. At least until Apple start fixing the memory leaks in MacOS.
I remember when Windows Vista had to contend against the same allegations when it was released. It did have a higher memory footprint, but a lot of the ridiculous usage numbers people had published were the SuperFetch just precaching commonly used programs to give better application startup times.
> I'm typing this on an 8 GB MacBook Air and it works just fine.
Most cool. Is it an M1?
It also compresses memory. Many things in ram compress really well.
What are you slicing?
What do you find compelling with Prusa slicer over orca slicer?
There's a lot of different kinds of "using". "Memory pressure" includes some kinds of caching (ie running idle daemons when they could get killed) and not others (file caching). And there are also memory pressure warnings (telling processes to try to use less memory), so there's a lot of feedback mechanisms.
I don't suggest sitting and looking at Activity Monitor all day. I think that is a weird thing to do as a user. If you would like to do that in an office in Cupertino or San Diego instead then you can probably figure out where to apply.
Indeed, as I used to tell my ops colleagues when they pointed to RAM utilization graphs, "we paid for all of that RAM, why aren't we using it?"