GreenLight enables scientific researchers to make 'green' data decisions by offering a suite of physical-layer architectures that leverage advanced middleware.  
The instrument provides 5 levels of optimization:

The Controlled Environment of the Container
This level employs a Sun Modular Datacenter (e.g. "Black Box") with instrumented rack space that is more "contained" than is typical for conventional computer centers and faculty "closet" clusters. It can measure temperature at 40 points in the airstream (5 locations on 8 racks), internal humidity and temperature, external temperature and humidity, incoming and exiting water temperature and power utilization in each of the 8 racks.

Open Instrument Through Web Services
Many sensor types are provided and data can be exchanged between the outside world and virtualization software through Service Oriented Architectures (SOAs).

Power/Temperature Controls
Each Black Box has 7 racks devoted to various types of clusters, plus one rack for switches. This configuration will enable GreenLight users to share and test computing resources as they pertain to applications, sensing, and feedback control algorithms for managing power consumption. The instrument's network switches can provide, using the simple network monitoring protocol (SNMP):

  • the amps, volts, and watts used by each linecard
  • total aggregate power available/used
  • power configuration, outlet and inlet temperature for multiple critical components on each linecard
  • cubic feet per minute cooling required per module
  • system fan status
  • aggregate traffic flows across the switch on a macro basis (for all large flows) in short and longer periods of time.

Alternative Hardware Architectures

  • clusters with multi-core processors
  • processor/arithmetical logic unit (ALU) arrays
  • specialized processing units such as graphics processing units (GPUs)
  • reconfigurable co-processing units using field-programmable gate arrays (FPGAs)
  • hybrid processing options
  • DC powered compute and storage servers (Intel and Sun).

Instrument Components
Components include processing units, memory, disk drives and network interfaces. 

Technical White Papers

Instrument Details 2011
Instrument Details 2010
Instrument Details 2009