Ming Mao, Jie Li, Marty Humphrey

eScience Group

CS Department, University of Virginia

Grid 2010 – Oct 27, 2010

A fast growing computing platform IDC - Cloud spending increases 27.4% a year to $56

billion (compared 5% a year of traditional IT)

$16.5 billion (2009) -> $55.5 billion (2014) src: Worldwide and Regional Public IT Cloud Service 2010-2014 Forecast

Two most quoted benefits

Scalable computing and storage

Reduced cost

Concerns

Security, availability, cost management, integration interoperability, etc.

Q1. Cost – the most important factor in practice?

Q2. Moving into Cloud == Reduced Cost ?

54.00%

63.90%

64.60%

67.00%

68.50%

75.30%

77.70%

77.90%

0.00% 20.00% 40.00% 60.00% 80.00% 100.00%

Seems like the way of future

Sharing systems with partners simpler

Alwasys offers latest functionality

Requires less in-house IT staff, costs

Encourages standard systems

Monthly payments

Easy/fast to deply to end-users

Pay only for what you use

Source: IDC Enterprise Panel, 3Q09, n = 263, Sep 2009

Rate the benefits commonly ascribed to the cloud on-demand model

72.90%

78.30%

79.20%

81.00%

82.10%

84.50%

86.00%

87.80%

88.60%

91.60%

0.00% 20.00% 40.00% 60.00% 80.00% 100.00%

Have local presence, can come to my offices

Are a technology and business model innovator

Offer both on-premise and public cloud services

Support many of my IT needes

Allow managing on-premise & cloud together

Understand my business and industry

Provide a complete solution

Option to move cloud offerings back on premise

Offer Service Level Agreements

Offer competitive pricing

Source: IDC Enterprise Panel, 3Q09, n = 263, Sep 2009

How important is it that Cloud service providers...

Resource utilization information based triggers (e.g.

AWS auto-scaling, RightScale, enStratus, Scalr, etc)

Multiple instance types

Current billing models Full hour billing

Non-ignorable instance acquisition time 7-15 min in Windows Azure

More specific performance goals

Budget awareness (e.g. dollars/month, dollars/job)

Deadline

(Job finish time)

Cost

Problem Statement – how to enable cloud

applications to finish all the submitted jobs

before user specified deadline with as little

money as possible using auto-scaling.

CloudApplication

Users

Job

Cloud Server

Workload are non-dependent jobs submitted in the job queue

FCFS manner and fairly distributed

Different classes of jobs

Same performance goal (e.g.1 hour deadline)

VM instances take time to startup

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Key variables used in the model

Workload

Computing Power of Instance

Running Instance

Pending Instance

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Scale up

Sufficient budget

Insufficient budget

Scale down

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( ')iMax P ( ') ( )i itype I type Ii ic C c

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Workload Required Computing Power

1

2

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21

: 60 10 10 40

: 60 5 20 35

: 60 20 5 35

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j x

j y

j z

P W I I

1

2 1 2 3

3

1 2 3

: 10 10 10 45

: ' 5 ' 20 ' 10 35

: 20 5 10 35

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j x

j n n n y

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Cloud Cruise Control

Decider

&

Monitor RepositoryVM

Manager

Config

VM instancesHistorical

Data

workload

dequeue

enqueue

update update

+ , –

vm plan

vm info

( ')( )itype Ii

Min c 'jjP W P admin

users

dynamic

configuration

notify

Mix

Avg 30 jobs/hour

STD 5 jobs/hour

Computing

Intensive

Avg 30 jobs/hour

STD 5 jobs/hour

IO Intensive

Avg 30 jobs/hour

STD 5 jobs/hour

General

0.085$/hour

Delay 600s

Average 300s

STD 50s

Average 300s

STD 50s

Average 300s

STD 50s

High-CPU

0.17$/hour

Delay 720s

Average 210s

STD 25s

Average 75s

STD 15s

Average 300s

STD 50s

High-IO

0.17$/hour

Delay 720s

Average 210s

STD 25s

Average 300s

STD 50s

Average 75s

STD 15s

Workload & VM simulation parameters

0.00%

10.00%

20.00%

30.00%

40.00%

50.00%

60.00%

70.00%

80.00%

90.00%

100.00%

0

1000

2000

3000

4000

5000

6000

7000

0 10 20 30 40 50 60 70 80

Utilization (%)Response (sec)

Time (hour)

Stable Worload & Changing Deadline

utilization deadline avg max min

0

50

100

150

200

250

300

350

0

500

1000

1500

2000

2500

3000

3500

4000

0 10 20 30 40 50 60 70 80

Worload (job/h)Response (sec)

Time (hour)

Changing Workload & Fixed Deadline

deadline avg max min workload

VM Types Total Cost ($)

% more than optimal

Choice #1 General 98.52$ (43%)

Choice #2 High-CPU 128.86$ (87%)

Choice #3 High-IO 129.71$ (88%)

Choice #4 General, High-CPU, High-IO 78.62$ (14%)

Optimal General, High-CPU, High-IO 68.85$

MODIS 200X – Year Terra & Aqua – Satellite

(X - Y) – Day X to day Y 15 images / day

Moderate scale test (up to 20 instances)

Large Scale test (up to 90 instances)

* C.H. – computing hour 1C.H. = 0.12$ in Windows Azure

1hour deadline 2hour deadline 3hour deadline

Terra 2004(10-12)

Total 45 jobs

4 C.H.* or 0.48$

18 min late 8 min early 20 min early

9 C.H.or 1.08$ 6 C.H or 0.72$ 5 C.H.or 0.6$

Aqua 2008(30-32)

Total 45 jobs

4 C.H. or 0.48$

15min late 20 min early 29 min early

10 C.H or 1.2$ 7 C.H.or 0.84$ 5 C.H.or 0.6$

2 hour deadline 4 hour deadline

Terra & Aqua 2006(1-75)

Total 1125 jobs

93 C.H. or 11.16$

20min late

170 C.H. or 20.4$

6 min early

132 C.H. or 15.84$

Terra & Aqua 2006(1-150)

Total 2250 jobs

185 C.H. or 22.2$

Admission Denied 22 min early

243 C.H. or 29.16$

Test: Terra & Aqua 2006(1-75) - total 1125 jobs

6min early

theoretical cost - 93 C.H. or 11.16$

actual cost - 132 C.H. or 15.84$

0 1 2 3 4 5

0

2

4

6

8

10

12

14

16

18

20

22

24

26

28

30

32

34

36

38

40

Time (hour)

Inst

an

ce N

um

ber

Instance Acquisition and Release

Released Acquiring Ready

Conclusions

More cost-efficient than fixed-size instance choice

VM startup delay can affect hugely in practice

Future works

More general cloud application model

Multiple job classes

Consider other instance types (e.g. spot instances &

reserved instances)

Data transfer performance and storage cost