BHyVe - ESXi comparison

[Peter Grehan]

Hi Andrea,

> We did a very rough comparison betweend BHyVe and VMWare ESXi. Maybe
> you want to give it a read and let me know if I did write a bunch of
> sh!t :-)

  Looks good to me :) Thanks for running the tests.

  Would you be able to list the command options you used with bhyve when 
running these tests ?

> What I couldn’t really understand (but that’s something not related
> to bhyve or VMWare) is how a multiprocessor machine is slower than a
> singleprocessor machine in doing the compilation… any idea?

  Is hyper-threading enabled on your system ? If not, then with a host 
only having 2 CPUs and a 2 vCPU guest, there isn't as much opportunity 
to overlap host i/o threads with vCPU threads.

  It would be interesting to see your "time" results when running bhyve 
to show %user/%system etc - that may give an indication of how much time 
is spent on 'overhead' CPU usage as opposed to pure vCPU usage.

 > 20 VM – 2 CPUs – 2GB RAM

  Interesting result to say the least :)

  I'll try and repro this and see if it's something simple. At first 
guess I'd say it's the classic 'lock-holder-preemption' issue that the 
ESXi scheduler has a lot of smarts to avoid.

  Another interesting test would be Qemu/KVM VMs on Linux to see if it 
has the same issue.

later,

Peter.