On 5/2/08, Andrew Lentvorski <[EMAIL PROTECTED]> wrote: > Tracy R Reed wrote: > > Brinkley Harrell wrote: > > > > > The next logical extension from here would be to move to VmWare's ESX > > > server and run a minimal hypervisor architecture and maximize the > > > vm's footprint space. > > > > For those who do not already know this is what xen is by default: a > > hypervisor. > > Now, I don't know what "minimal" means, but Xen struck me as being far from > qualifying as minimal.
I don't think the connection was being made between "xen" and "minimal;" just "xen" and "hypervisor." A hypervisor is technically just a system of virtualizing the processor at the hardware level and not from within an operating system. Some amount of processor/RAM is taken up by the hypervisor itself, but much less than attempting to run a full OS as a virtualization host. VMWare ESX (and especially ESXi) bill themselves as "bare metal" hypervisors, and attempt to provide resources to multiple guests while requiring as little power themselves as possible. ESXi purports to need only 32MB of RAM. A couple of years ago, when Intel was first coming out with chips that support hardware virtualization, there were actually a rash of rootkits that installed themselves as hypervisors so that they were supposedly unable to be seen from inside a running OS. The most famous, and first successful, of these exploits was called "Blue Pill" (so named, apparently, because it kept the machine within an undetectable "Matrix"). From what I heard and read at that time, it appeared to have affected Windows primarily or even solely. By the way, since Linode has been mentioned recently: my personal server is a VPS from Linode, and I've really liked it. Linode currently uses a homegrown version of UML, but they just completed testing for Xen and will be rolling it out to their hosts over the next several months. -- Brad Beyenhof http://augmentedfourth.com Have the courage to be ignorant of a great number of things, in order to avoid the calamity of being ignorant of everything. ~ Sydney Smith, English essayist and preacher (1771-1845) -- [email protected] http://www.kernel-panic.org/cgi-bin/mailman/listinfo/kplug-list
