bhyve issues on Dell C6220 node

[Yamagi Burmeister]

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.

Regards,
Yamagi

-- 
Homepage: https://www.yamagi.org
Github:   https://github.com/yamagi
GPG:      0x1D502515
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 833 bytes
Desc: not available
URL: <http://lists.freebsd.org/pipermail/freebsd-virtualization/attachments/20200109/2145fd9d/attachment.sig>