ULT the OOM killer (and the kernel’s memory management in general) is one of the biggest annoyances with Linux for me, having used Macs for decades and *knowing* that we don’t have to still handle memory shortages like it’s 1975 any more

I’m pretty sure Mac OS inherited its ability to swap out to any available disk space from Mach, which came out in 1985

@dpk As someone who switched from Linux on desktop to a MacBook a few months ago, I find it completely absurd and annoying how Linux sometimes handles certain things :>

@dpk what's the difference between MacOS/Linux here, I don't follow? Is it that Linux needs a preconfigured fixed size swap partition / file?

@fraggle See retooted thread https://mastodon.social/@verdre/116182376380456569

Yes, Linux (without a third-party hack in userspace) needs fixed-size pre-allocated swap space. But also, Mac OS won’t kill processes just because it’s running out of memory; it will pause them instead (as if by SIGSTOP)

@dpk @fraggle

Yes, Linux (without a third-party hack in userspace) needs fixed-size pre-allocated swap space.

As far as I know on MacOS dynamic swapfile creation is also handled by a userspace process. Not a third-party one, but on Linux everything in userspace is third-party since Linux is just the kernel. I don’t see how swapd is any more of a hack than MacOS’s dynamic_pager.

Mac OS won’t kill processes just because it’s running out of memory; it will pause them instead (as if by SIGSTOP)

How does SIGSTOP help if you’re out of memory? It won’t free anything.

@noisytoot @dpk if a process is continually allocating more memory, SIGSTOP will prevent it from allocating any more. Also a stopped process can be entirely paged out to disk; a process that's still being scheduled will cause thrashing as its pages will keep being brought back into RAM