bhyve issues on Dell C6220 node

[Matt Churchyard]

Hi,

> >2016 is slow (even slower doing windows updates).  2019 is much better.  A tip I have found is a minimum of 1 cpu, 2 cores and 4 threads to get decent speed from that OS (more CPUs in bhyve >tends to make performance worse - in my observations - in 2016).  Also, use the Virtio collection from RedHat for vionet and viostor.  We are currently using 0.1.171 without issue.  The ahci >emulation in itself is extremely slow.  NVMe and virtio is really the only way to go.
> 
> Is there anything else I can check here? I haven’t got round to testing networking yet but I’m using nvme for the disk.
> It’s basically unusable and there is no way I could put anything production on it. Just highlighting an icon on the desktop takes several seconds.

>Windows is slow when running on Intel CPUs that don't support APICv.
>That are (nearly?) all desktop CPUs, all Xeons before Sandy Bridge and some Xeons after it. The problem is that Bhyve doesn't implement TPR shadowing. I'm >currently working on it. The review can be found
>here: https://reviews.freebsd.org/D22942 The speedup is about factor 6!

>I've received some feedback in a private mail, a second version that adds TPR thresholds can be found in my Github branch here:
>  https://github.com/Yamagi/freebsd/commits/wip/tpr_shadowing 

>A backport to 12.1 (the branch also includes the Intel SpeedShift patches from https://reviews.freebsd.org/D18028) is here:
>>https://github.com/Yamagi/freebsd/commits/production/12.1

>I've applied it to 2 of my production servers about 4 hours ago. Looks good so far. I'll update the review when I'm sure that it doesn't break anything, maybe >early next week.

Thanks Yamagi,

That's brilliant and provides me some hope that I may not have to completely abandon windows guests after all...

These servers are just sat next to my desk in testing at the moment so I'll see if I can have a go at applying the patches and testing it in the morning.

Regards,
Matt