Possible causes for "Resource temporarily unavailable"?

[Silas <silas_nbl%silas.net.br@localhost>]

Hello.

I'm running some small number of NVMM virtual machines. Sometimes one of
them just get killed with:

	qemu: qemu_thread_create: Resource temporarily unavailable

dmesg shows:

	pid 4381 (qemu-system-x86_): user write of 3221100864@0x76db1c5ce000 at 5314544 failed: 27


Number of process is low:

	$ ps aux | wc -l
	116

But number of LWPs is high:

	$ ps aux -s | wc -l
	1209

I'm running three instances of Firefox, they sum up 931 LWPs:

	$ ps aux -s | grep firefox | wc -l
	931

I tried to increase LWPs in sysctl with no success. It seems it is
hardcoded into the kernel code? Setting a new limit for threads (ulimit
-r) also doesn't work.

Well, not sure if number of LWPs is the problem, but I thought it was a
good idea to add this information here. It would explain why sometimes
one of my firefox instances gets killed randomly.

	$ uname -a
	NetBSD hope 9.2 NetBSD 9.2 (GENERIC) #0: Wed May 12 13:15:55 UTC 2021  mkrepro%mkrepro.NetBSD.org@localhost:/usr/src/sys/arch/amd64/compile/GENERIC amd64

Any help? Thanks!