Red Hat approach to Xen has been very confused so far.
Now, after release of first enterprise distribution, RHEL 5, featuring the open source hypervisor for the first time, tech magazine are starting to publish their reviews.
First one is from SearchServerVirtualization which details the guest OS creation and installation process, highlighting som glitches:
…
At this point, the installation is just like a standard installation of the OS. There is, however, one tricky point in the process. After you go through all the standard screens asking for your time zone, etc., you are presented with a final standard installation screen asking you to begin the final install. At that point, the console window you’ve been working in disappears! You then need to go to the host OS shell and execute “xm create guestname”, which in our case the entire string was “xm create RHELguest1″…
NetworkWorld goes further, comparing Xen implementation of Red Hat Enterprise Linux against Novell SUSE Linux Enterprise one:
..we found, is that Red Hat’s Xen implementation is far more evolved than what we found in SUSE 10, although it does lack comprehensive instrumentation.
…
When we tested the RHEL5 native kernel for performance (using OS install time-chosen defaults, as we normally do) against SUSE 10, we found little notable differences in our LMBench results.
…
The impact of introducing Xen’s hypervisor to the subsequently Xen-ified RHEL5 kernel represented only nominal latency from the native RHEL5 results. We measured the Xen impact on performance, and found that the ‘insertion loss’ of the hypervisor layer and ‘Xenified RHEL5 kernel’ are nominal: performance isn’t affected much. Adding guest operating systems to the Xenified RHEL5 kernel dragged down performance…