[emulators/VirtualBox]: System unresponsive/unusable with CPUs with more than 4 physical cores

[O. Hartmann]

Running emulators/virtualbox-ose (most recent due to daily ports updates and
daily kernel/kernel-module compilations) on 11.0-CURRENT FreeBSD 11.0-CURRENT #2
r287433: Thu Sep 3 15:14:30 CEST 2015 amd64 ontop of a 6-Core XEON Haswell:
CPU: Intel(R) Xeon(R) CPU E5-1650 v3 @ 3.50GHz (3491.99-MHz K8-class CPU)
Origin="GenuineIntel" Id=0x306f2 Family=0x6 Model=0x3f Stepping=2.

I realise a very strange behaviour on ALL VBox systems we run on FreeBSD since
9.0 that do have more than 4 physical cores. No matter how many cores I
delegate to a guest system (Windows 7), the 6 or 10 core XEON systems (12 or 20
logical cores) starts getting irresponsive, dramatic slow and within the Guest
and outside USB mice become highly jumpy and not very responsive.

Compared to a reference box running the very same OS revision, but with a
low-end 4-core XEON with only 4/8 physical/logical cores, the system is
dramaticallt slow. A system update of the guest was performed within 2 minutes
on the small XEON e3-12XX Haswell (16GB RAM), it is still running after 75
minutes on one of the 6-core systems (technical specs as shown above) (with
32GB RAM).

Is there a known issue (couldn't find something useful via Google) with FreeBSD?


Regards,
Oliver