[Planetlab-devel] The end of microkernel Hypervisors (Xen/VMware ESX) in sight?

[Marc E. Fiuczynski]

Stephen Soltesz pointed out that a patch will be included in Linux 2.6.20 to
support Intel VT and AMD Pacifica support
(http://www.heise.de/english/newsticker/news/82344/from/rss09), which will
let the Linux kernel act as the hypervisor and unmodified guests such as
Windows/Solaris/etc run as "special" processes.  This evolution from
microkernel-style hypervisor (i.e., Xen) towards monolithic Linux hypervisor
reminds me of the transition from Windows NT 3.51 towards a unified Windows
NT 4.0.  While a microkernel solution certainly is more elegant and
flexible, it seems that the world is more comfortable with monolithic
solutions (somewhat similar to the CISC vs. RISC battle).  What does this
mean in general?  Well, it could very well signal the end of
microkernel-style hypervisors.

The article also claims that this addition to the Linux kernel signals the
demise of OpenVZ and Vserver (i.e., the style of virtualization that
PlanetLab uses), which I don't agree with. I firmly believe that these are
complementary technologies. In fact, I think it opens the door to explore
several new points in the virtualization design space.

What are the implications for PlanetLab (and its successors)?  Not sure yet,
but exciting times wrt systems software are definitely on the horizon.

Marc