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Holistic Approaches to Green IT. Going Green Can Save Money. Dr Hugh Beedie CTO ARCCA & INSRV Cardiff University. Introduction. What is Green IT ? Drivers & Metrics Data Centres, Power & Cooling Servers, Virtualisation, and Storage PCs, Monitors & Thin clients Printing and Networks
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Holistic Approaches to Green IT Going Green Can Save Money Dr Hugh Beedie CTO ARCCA & INSRV Cardiff University
Introduction • What is Green IT ? • Drivers & Metrics • Data Centres, Power & Cooling • Servers, Virtualisation, and Storage • PCs, Monitors & Thin clients • Printing and Networks • Purchasing policies • Influencing user behavior & the organisation • ‘Thinking outside the box’ – save energy with Condor
What is Green IT ? No environmental impact Get real Use of resources in an efficient way Better Avoid ‘Greenwash’ Often faulty comparisons Importance of your Context Your situation, drivers & metrics… Can change over time
Drivers – Why do Green IT? • Increasing demand for CPU & Storage • Lack of Space • Lack of Power • Increasing energy bills (oil prices doubled) • Enhancing the reputation of your University & attracting better students • Sustainable IT & Legal Compliance • Because we should (for the Planet )
Metrics – Chicken and Egg You can’t measure everything. So, which numbers do you measure, when you don’t know which are important ?
Guesstimation • Which use more, PCs or Servers ? • 10,000 PCs using • 150W, 8 hrs/day, 220 days/yr • UK electricity £300,000 p.a. • 500 servers using • 300W + losses (X 2) • 24 X 7 • UK prices £300,000 p.a. • So where do we start ?
Examples of Metrics • Cost (Watts, TCO, capital investment, etc) • Value (CPU Hrs, MFlops, Gbps, Papers) • Value/Cost is better ? (MFlops/Watt) • Cooling & power losses (PUE) • Average kWhr per PC per year • Pages printed (or not printed ?) • Cost per page (electricity, paper) • Space saved
Power Usage Effectiveness • PUE=Total Power/Computer Power
The DetailWhat wastes the power ? • Power Conversion in HV Transformer • Before it gets to your room, you lose power.Transformer Efficiency = 98% or 95% • Return On Investment (ROI)? • Capital Cost = £5500 or £5000 (650kVA) • New installation (@200kW), ROI = 1 month • Replacement, ROI = 1 year • Lifetime of investment = 20+ yrs !!!!!
25.5% Room cooling system70W 7.3% UPS +PDU 20W 5.5% Server fans 15W 18.2% PSU 50W 7.3% Voltage Regulators20W 36.4%Load CPU, Memory,Drives , I/O100W Total 275W 100% Cooling Source: Intel Corp. 80% Powerdelivery Cumulative power 40% Loads Data Centre Consumption Bull View Intel View
Hot Aisle Containment Hot Aisle Ceiling Tiles/Cable Trough Seals in hot air, prevents mixing with room air Chamber DoorsAccess to hot aisle, locks for security. Prevents hot air mixing InRow RC unit InRow air conditioner cools hot exhaust air directly
Rack Air Containment Airflow Diagram Server exhaust air is prevented from escaping by rear containment All exhaust air is returned to InRow cooling unit Fans of InRow cooling unit distribute cool air to front of IT equipment Rear Rear Containment NetShelter SX Rack InRow CoolingUnit InRow Cooling Unit Servers Front Containment Front Top Down View
Temperature (deg C) <24 27.4 30.8 34.3 >37.8 Cooling Inside the Room • APC Inline RC units • Up to 20kW/rack • Uniform cooling allows raising cold air temp
Cooling – Outside the Room 3 Airedale Chillers Ultima Compact Free Cool 120 Quiet model Variable speed fans N+1 arrangement (We needed that )
Free-cooling System operated on mechanical cooling only(38% of Year) System operated on 100% Free-Cooling (12% of Year) System operated on partial Free-Cooling (50% of Year) Cooling Load -7oC 3.5oC 12.5oC Mechanical (compressor) cooling Ambient Temp. Free-cooling
Back Up Power APC 160kW Symmetra UPS • Full and half load efficiency >92% • Scalable & Modular – could grow as we grew, keeping %max load high
High Density Servers Important if you spend on advanced cooling methods Can have shared power supplies (PSU) Higher efficiency Blade Servers have shared PSUs Not always good for HPC Bull supplied half-width, 1U servers. 2, quad core, 80W Harpertown CPUs
Cardiff’s PUE vs Temperature Average PUE = 1.3 No correlation with temperature ?
Key Power Saving Solutions HVTransformer Modular UPS 98% efficiency (not over provisioned) Cooling Infrastructure “Air Handling” Chilled Water Low power servers High Density Servers(sweating the asset)
Virtualisation and Storage • Virtualisation • Many virtual servers in one physical server • Key questions • How much can you save ? • How much of that is energy ? • Storage • Fast disk=450GB, 25W, Slow disk=2TB, 15W • Tiering = Energy saving
Business CaseBefore Virtualisation * Inefficient raised floor and ceiling mount air conditioning units
Business CaseAfter Virtualisation * Inefficient raised floor and ceiling mount air conditioning units
Virtualisation Business Case3 Year ROI with Virtualisation Hardware £959K Electricity £368K Total Savings = £1.32M
Planet Filestore JISC-funded project to measure savings of.. Tiered storage – scenario 100TB needed for 30000 (staff and students) High performance for 7000 concurrent users Site mirrored Raid 10 450GB SAS vs Non mirrored Raid 5 2TB SATA ~ factor of 16 in hardware cost Therefore, use HSM (old data on Tier 2) What about energy ?
Planet Filestore Project Fast disk (FC/SAS) 450GB, 25W Slow disk (SATA) 2TB, 15W Tiered storage Tier 1 – DR Tier 2 – non DR 100TB Tier 1 (DR) Energy cost £25,000 p.a. 10TB Tier 1 (DR) 90TB Tier 2(nonDR) Energy cost £3,250 p.a. Energy saving = £21,750
PCs & Monitors • Where to start ? • Duty cycle guesstimate • Always on (100%) • On during working hours (20%) • Turn it off at night !!
What next for PCs ? • More stringent power saving policies • Asset Management (reporting) • Influencing user behaviour (Joulemeter)
What about Thin Clients ? Still some scope, but notwhat there used to be
Printing • Thanks to Liverpool John Moores University (LJMU) for the next 2 slides
Carbon Footprint Savings • Hundreds of devices removed • Old lasers • Deskjets • Fax machines • Replaced with fleet of 220 devices • Automatic power saving after 2 hours • Use of recycled paper • FollowMe documents held for 18 hours
Actual Savings at LJMU 2007/8 ~£80,000 Approximate three year saving 2008/9 ~£100,000 £310,000 2009/10 ~£130,000
Networks • Power used by switches • 3.5Gbps/W to 0.5Gbps/W • Cardiff LAN has 50,000 outlets • 100kW down to 15kW • Potential £85k p.a. by choosing well • PoE (up to 25W down a UTP cable) • 5W in the cable, 5W DC-DC conversion • 40% loss
Purchasing Policies • Use EnergyStar PCs • Discourage use of the fastest PCs • Use energy in your TCO calculations • Ensure suppliers only publicise green PCs
Influencing Behaviour • Context – who pays for electricity • Target your messages • Users • Their PC uses ???W • Pages printed last week ?? • Technical types – detail • MFlops, kW, Geeks/Pint • Managers • Bottom line ££££ • Reputation.
Finally…. What is Green, but makes your PC use more electricity ? Answer – Condor So, what is Condor ? Condor takes spare CPU Cycles for use in Research calculations Runs at low priority so users don’t notice So why is it Green ?
Conclusions • Measure, Improve, Measure again • Look everywhere for waste • Context changes over time • Make sure you revisit your assumptions • Don’t just do the technical stuff • Think out of the box (Condor)
Cardiff’s New Datacentre • £3M grant to purchase a supercomputer • New Datacentre required with appropriate power, cooling .. • Our Context ? • INSRV Sustainability Mission - To minimise CU’s IT environmental impact and to be a leader in delivering sustainable information services. • Limited experience in Datacentre build • Server & Data Center Energy Efficiency(US Congress Report 2007)
What did Cardiff do ? • Ran 2 tenders, many contractors (& subs) • HPC & Environment (power, cooling) • Strong project management • TCO as key evaluation criterion • Value = HPC Benchmark figures • Winner = Highest Value/TCO