[nzentzis]

I just tested this on my Linux workstation.

2000 threads does nothing - everything's still responsive, and the process is shown as using 0% of the CPU.

16,000 threads uses ~30% of a core, with a ~136MB RSS. The system still handles it fine, though, and everything stays responsive.

At 20,000 the program panics when spawning threads, with the message "failed to set up alternative stack guard page" due to EWOULDBLOCK. I'm not sure exactly what limit it's hitting, though.

[OskarS]

Sounds like it's having trouble allocating memory for the stack and stack guard. Whatever limit it's hitting though, Linux seems to be able to handle it correctly, which is to kill the process instead of a kernel panic.

[DerDangDerDang]

Thanks, much appreciated.

That’s the sort of thing I expect - the OS starves the program, not the other way around.