Ryzen issues on FreeBSD ? (with sort of workaround)

[Don Lewis]

On 24 Apr, Mike Tancsa wrote:
> On 4/24/2018 10:01 AM, Pete French wrote:
>> 
>> Well, I ranh the iperf tests between real machine for 24 hours and that
>> worked fine. I also then spun up a Virtualbox with Win10 in it, and ran
>> iuperf to there at the same time as doing it betwene real machines, and
>> also did a full virus scan to exercise the disc. the idea being to
>> replicate Mondays lockup.
> 
> I was able to lock it up with vbox. bhyve was just a little easier to
> script and also I figured would be good to get VBox out of the mix in
> case it was something specific to VBox.  I dont recall if I tried it
> with SMT disabled.  Regardless, on Intel based systems I ran these tests
> for 72hrs straight without issue.   I can sort of believe hardware issue
> or flaky motherboard BIOSes (2 ASUS MBs, 1 MSI MB, 3 Ryzen chips), but
> the fact that two server class MBs from SuperMicro along with an Epyc
> chip also does the same thing makes me think something specific to
> FreeBSD and this class of AMD CPU :(

It would be interesting to test other AMD CPUs.  I think AMD and Intel
have some differences in the virtualization implementations.