Datacenters have been reducing their Power usage effectiveness (PUE) for years now. It has become an important factor, which can generate a lot of good PR. The PUE is defined as being equal to the sum of facility power and IT equipment power divided by IT equipment power. Facility power got most of the attention, but while datacenters have been reducing their PUE from roughly 2-4 to 1.2-1.5, the customers of the datacenters hardly know where to start. Yes, despite all the talk about green IT, few companies with large outsourced IT infrastructures have been able to reduce the energy bill. Server sprawl has been slowed down but was not stopped by virtualization and few people have taken the time to study the problem. So we felt it was to time for the Sizing Servers Lab to step in and do our share. 

On the first October we started with our IWT approved project "Saving Energy in the IT infrastructure". We will try to lower the energy consumption inside the rack at 5 levels:

• Software tuning in both the development stage as in the configuration phase.
• OS power management optimisation (ACPI)
• Optimal hardware choice
• Optimal virtual cluster settings (DRS for example)
• Optimal physical cluster settings

No less than 17 flemish companies and institutions decided to partner with us to battle this problem:

• Combell, one of the largest hosting firms in the Benelux is a big customer in many datacenters. 
• UZ Gent and Agfa however have their own large datacenters and have thus control over both the IT equipment as the facilities.
• Racktivity is the innovator behind the Energyswitch products. The Energyswitches allows us to measure energy accurately and helps us to control energy consumption. 
• A-server is the company of the SmartStyle Office, an all in one office solution. We work with A-server to further improve the energy efficiency and performance of their product.
• D&N is our partner in "Green software". Well optimized software can reduce the energy consumption by 5x and more. Thanks to Intel, we now have even a software tool that allows to measure energy efficiency of software.  
• Hexios and Savaco are capable integrators which allow to understand what companies actually expect from their infrastructure.
• A.N.S. sells IT equipment material and is thus an another interesting source of market information.  
• RIS is a local service and hosting provider that is constantly seeking to improve their efficiency.
• Ecopuur is driven by ecological and energy saving values and wants to apply the same philosophy to its IT infrastructure.
• EnergyICT is a world renown energy management company. 
• The datacenter departement of Ingenium consist of the seasoned architects of several datacenters. Being one of the first European "Code of conduct for data centers" endorsers, Ingenium offers us a different way to look at the energy consumption problems of the datacenter.
• If we save a lot of energy inside the rack, these savings must also result in facility savings. That is the task of datacenter owner LCL: helping us understand the impact that the IT equipment has on the rest of the datacenter. 

VITO's Energy technology departement has been researching green technologies for a long time and University Gent research group ELIS is specialized in the hardware/software interface.

An impressive and long partner list means very little without some realworld results. We are of course at a very early stage of the research, but you can already find some of the bits of our research here. By custom tuning the power management of ESXi, we could sometimes significantly lower the power consumption at low/idle load:

Notice how AMD's newest "Interlagos Opteron" server platform consumes 20% (!) less thanks to a customized power management policy. We will report more as our research starts to produce more and more results.