That limitation appears to still exist in FreeBSD 13.0-RELEASE:
[root@grit] # freebsd-version -k ; grep 'VM_MAXCPU'
/usr/src/sys/amd64/include/vmm.h
13.0-RELEASE
#define VM_MAXCPU 16 /* maximum virtual cpus */
I ran into this in May 2021 and with some help from folks on this list
was able to increase it. The simplest (if not minimalist) way to do that
is:
1. edit /usr/src/sys/amd64/include/vmm.h to increase that value: I used
48
2. make buildworld
3. make installworld
The increased value has been working fine for me since I did that. I run
a couple of VMs with 24 vCPUs each and several others with smaller
numbers all the time and have run others with as many as 48 temporarily.
No problems that I have seen.
I don't use cbsd so can't comment on that.
On Wed 2021-12-01 04:24 AM MST -0700, <jbo@insane.engineer> wrote:
Hello folks,
I'm using the sysutils/cbsd port for managing bhyve VMs on multiple
hosts.
CBSD does currently not allow to assign more than 16 vCPU cores to a
VM.
I've reached out to the CBSD author(s) to check up on this situation.
I was
referred to an E-Mail from this mailing list from 2014 at which point
this was
apparently a bhyve limitation.
I'd like to understand whether this limitation is still present to
this date. Or
whether bhyve is able to assign more than 16 vCPU cores to a VM?
Thank you for all your hard work & Best regards,
