[z92]

When does GC kick in during the boot sequence? And how are you managing memory? Is the whole OS mark and sweeped?

[ffwff]

Right after the global descriptor table is setup and paging is enabled, the GC is then enabled. On every allocation, and whenever the os has no task available to switch to, a gc cycle is performed.

Not really, the kernel and any process written in crystal has a garbage collector, any other userspace process can manage memory however they want to.