On Wed, April 30, 2008 4:59 pm, Tracy R Reed wrote: > Lan Barnes wrote: >> I'm confused (in Linux) on how this saves, since I would expect that >> throughput, memory, and context switching on VM boxen would _at best_ >> only >> equal running all those services on one box. What am I missing? > > Sure. But the vast majority of our servers are idle 99% of the time. The > stuff sits on separate servers mainly for reliability and > maintainability reasons. Also sometimes we need different versions of > stuff, as you pointed out in your previous post about CM. We only need > the rare burst of speed and it's very unlikely that any two machines > need that burst of speed at the same time. > >> Doesn't it add up to the same number of instructions per time uint, the >> same memory load, the same disk space (except VM should need marginally >> more for context switching)? > > Yep. Except we can do it all on one motherboard and power supply and > unit of rack space instead of spreading it out over many. >
But in Linux/fbsd/etc, I'm still puzzled in how this is superior on straight servers to just running a bunch of services on one box, and forget the xen? I get it in windoz, although running Linux build machines on a VMWare windoze box (as we do at work) strikes me as throwing out the baby and keeping the bathwater, and, yes, it does screw us from time to time when IT pushes a windoze upgrade and crashes the Linux build VM. -- Lan Barnes SCM Analyst Linux Guy Tcl/Tk Enthusiast Biodiesel Brewer -- [email protected] http://www.kernel-panic.org/cgi-bin/mailman/listinfo/kplug-list
