some interesting observations on the relative performance of kvm vs. bhyve

[Peter Grehan]

 > I have 1 host that dual boots FreeBSD and Ubuntu 12.04.3 LTS and bhtyve
> seems to be atleast 3 or 4 times faster with disk I/O then kvm using the
> most stripped down command lines I can come up with.

  I'm guessing that the default cache mode for qemu in that release is 
"none". You may want to switch it to "writeback", which is what bhyve 
does by default (it can be changed with AHCI, see bhyve(8)).

  Lots of info on the web about Qemu block i/o cache modes e.g.

 
http://pic.dhe.ibm.com/infocenter/lnxinfo/v3r0m0/index.jsp?topic=%2Fliaat%2Fliaatbpkvmguestcache.htm

later,

Peter.