•StratusLab is co-funded by the•European Community’s Seventh

•Framework Programme (Capacities)•Grant Agreement INSFO-RI-261552

Ioannis KonstantinouGreek Research & Technology Network and

National Technical University of Athens, ikons@cslab.ntua.gr

Evangelos FlorosGreek Research & Technology Network

efloros@grnet.gr

Nectarios KozirisGreek Research & Technology Network and

National Technical University of Athensnkoziris@cslab.ntua.gr

Public vs Private Cloud Usage Costs:

The StratusLab Case

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Q&A

How much does it cost to build your cloud?TCO calculation

When and how public clouds make money?Break even point calculation

What is cheaper: build and own a private cloud, or renting it in Amazon?StratusLab caseActual usage traces from 11/2010 until 11/2011

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The StratusLab project 1/2

2 year EU funded started in June 2010an IaaS platforman open source distribution

Automatic IaaS cloud setups

Focus on automatic virtual Grid Site deployments

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The StratusLab Project 2/2

VM managementOpenNebula cloudKVM hypervisor

• Claudia– Monitoring – Elasticity

based on KPI

• Disk Management– Pdisk service– iSCSI

interface

• Marketplace– Set of digitally

signed VM images

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Physical Infrastructure Description

Athens datacenter completed in 20104 racks with 32 servers each¼ dedicated to StratusLab1 rack plus few TBs of EMC storage

StratusLab cloud physical machines18VM containers + 1FrontEnd + 4 testbed + 1 DHCP

– Dual QuadCore E5520 Xeon with Hyperthread 2x4x2=16VCPU each

– 48GB RAM and 2 RAID1 SAS Disks

– A total of 16x18=288 CPU available for VM usage

GB Network for servers and FC with the storage280TB EMC Celera NS-480 storage

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TCO calculation

Cost Categories break-down inHardware and InfrastructurePower ConsumptionManpower

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TCO: Hardware and Infrastructure 1/2

8K€ per server including network, storage and dc infrastructure cost5 year warranty, non linear depreciation rate In 2 years, 60% value decrease

Server cost: 24 x 8K€ x 60%=115.2K€

Network line costFlat-rate 2 x 10GbE lines result in 30K€Negligible GEANT network expenses

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Power Consumption CostMonitoring period between 11/2010-11/2011Actual Watt measurements from VM containers using

the IPMI interfacesAssuming an 1.8 PUE valueMultiplied by the energy provider’s tarrif

A total of 6.6K€ for 2 years

TCO: Hardware and Infrastructure 2/2

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TCO: Manpower costs

1 DC administrator with a yearly salary 40K€25% commitment to StratusLab for 2 years2 x 40 x 25% = 20K€

2 people for site admin and management20K€ each for 2 years resulting in20 x 2 x 2 = 80K€

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TCO summing up

• A total of 251.8K€

• Including support hardware

• Open-source software, no license fees

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Break-Even point calculation

Based on the calculated TCO, the hourly cost of service hosting is 251.8K€/(365days∙2years)/24h≈14.37€/hour

For a total of 288 cores and an average utilization of 70%, a single core VM costs14.37€/(288 ∙ 0.7)=0.0712 €/core

For the above price, the cloud would amortize its cost in two years time (zero profit)

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Use Case: Virtualized Grid Site

Part of the EGI under the control of GRNET

Core grid services provisioningA CE, 16WN, a SE with 2TB and APEL serviceEach WN has 2CPU and 4GB RAM

Since Jul 2011 support for 18VOs incl. high energy physics (ALICE and ATLAS) biomedical (Biomed) Com. Chemistry etc.

31,781 jobs requiring 11,655 wall clock hours with 28,321h normalized CPU time

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Public Cloud Cost Analysis

MethodologyExtract Computing, Storage and Memory consumption

stats from usage log filesAccording to consumption, calculate how much it would

cost to run it on Amazon

StratusLab VM hardware resembles Amazon’s t1.small and t1.micro instances t1.micro hourly rate in Dublin: 0.019€ t1.small hourly rate in Dublin: 0.07€EU/Dollar rate and Amazon prices in Nov 2011Per hour pricing, not reserved or spot instances

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Charge types

CPU Cost EC2 cost for Amazonbreak even cost for StratusLab

Storage Cost (EBS + S3)No EBS, we consider local volatile disksNo need for S3 storage

Network CostAmazon Charges only for in/out trafficFree traffic between Amazon servers

Therefore, only CPU cost

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StratusLab vs Amazon Costs 1/2

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StratusLab vs Amazon Costs 2/2

t1.micro is cheaper, but micro instances are overcommitted

t1.small price the same as the break-even

By the end of the year, 20% of TCO has been amortized

After a couple of years the full TCO will be amortized

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Conclusions

A small scale private cloud is amortized in 2-3 years

In StratusLab the break-even cost for self-funding the service is the same with EC2Slower amortization can achieve cheaper rates

Economies of scaleThe larger the cloud, the faster the amortization

Utilization is very importantCPU cycles cannot be wasted

Compute-demanding apps are expensiveBest for private clouds

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Questions?

•http://www.stratuslab.eu