Computer Room Provision in Atlas and R89

1. Computer Room Provision in Atlas and R89 Graham Robinson

2. Computer rooms built 1960/70’s Housed numerous computers including several super computers such as Atlas, IBM 360/195, Cray X-MP, Cray Y-MP and Cray J90 Apart from specials, such a freon cooling, power and air conditioning infrastructure sufficient until 2004 Refurbishment started in 2004 aimed at meeting forward projections to 2012 of which TIER1 are a major constituent Forward projections basis of the business casefor new computer building – R89 Atlas Centre – The Past

3. Air conditioning system refurbished to improve efficiency and reliability but still needs bi-annual maintenance shutdown New computer room access control system installed and security improved Fire detection system modernised but no fire suppression added. Fire brigade 3 minutes away A5 Lower cleared to make space for new high power systems Unused computer rooms brought back into service to house displaced computers Atlas Centre Refurbishment

4. All new high power systems to go in this room Floor strength augmented to support heavy racks New 960kW air conditioning system installed solely for this room with independent units so can run 24 * 7 Power Density raised from 0.5kW/m2 to 1.9kW/m2 860kW of additional power installed for computers with more available if need be Security improved Atlas CentreRefurbishment of A5 Lower

5. Estimates for TIER1 and HPC systems to 2012 Trends in heat output noted over several years ASHRAE projections on future heat trends (~5% increase/annum) used Dual and Quad core CPU chips lowering heat output New “twin” systems double heat output but halve the rack count. Net load the same but more concentrated Configuration unknown until 6 weeks before delivery So always plan for worst case When systems in production heat output of CPU systems usually less than maximum Future Projections

6. A5 Lower modelled by Flomerics using CFD Identified hot spots and heat flow characteristics Expensive and slow – what if? not easy to do Spreadsheet model based on performance data of air conditioning units developed over the last year Gives instant answers to what if? questions Used to evaluate layouts and check resilience Model recalibrated after each new installation Can extrapolate into future but with care Computer Layout Planning

7. In A5 Lower we will have: 390kW of spare air conditioning 380kW of spare power Space for at least another 30 racks TIER1 FY08 estimated at 190kW and 22 racks so could go into Atlas but modelling indicates it would reduce air conditioning resilience Atlas Centre Estimated status by September 2008

8. Started construction - completion date Sept 2008 Designed to be secure – strong construction, minimum entrances, ram raid protected and overlooked by the main gate Security staff Fire detection and suppression in partitioned areas 5 MW total power Over 2MW of air conditioning using chilled water Power Density of 3.0 kW/m2 is the target in the main computer room Space for 300 racks 600mm wide Space for up to 5 tape robots R89 New Computer Building

9. Two floors of offices for computer support staff Combined Heat & Power unit reduces carbon footprint Computer room capacity should be OK up to 2012 unless we get more systems to house Chilled water ring main to support local water cooling of racks will allow us to go to more than the 15kW per rack we currently limit ourselves to Designed to be expandable so could add more chilled water capacity (most likely first shortfall) and double the space capacity Atlas is the backstop! R89 New Computer Building