I am planning on doing some major maintenance work tomorrow.  First will be the installation of our newest server.  This should not disturb existing services but there is always the potential for operator error.

     The second thing I will be doing, and this WILL result in downtime for various services, is to take the various physical servers down for some time to do some BIOS tuning.  The idea is to switch from a fixed CPU voltage to a variable voltage that changes with clock speed so that during times of low load on a given machine, power consumption and heat production will be less.

     CPUs require more voltage to be stable at higher clock frequencies.  All of our modern machines change clock rate with load up to some defined maximum, but presently are using a fixed CPU voltage which is suitable to the highest load.  This change will have them change their core voltage with clock frequency as necessary for the frequency they are operating at during any given time.  This will require some benchmarking and load testing to optimize.

     This will not change the peak capabilities of the machines significantly.  It may allow them to clock slightly higher than normal for brief intervals if hit with a sudden load when idle and cool because of the thermal mass of the CPU cooler, but mostly it will affect only the low load and idle conditions.