Addressing Strategic Behavior in a Deployed Microeconomic Resource Allocator

Chaki NgChaki Ng (Harvard) (Harvard)

Co-Authors: Phil Buonadonna, Brent Chun (Intel Co-Authors: Phil Buonadonna, Brent Chun (Intel Research), Alex C. Snoeren, Amin Vahdat (UCSD)Research), Alex C. Snoeren, Amin Vahdat (UCSD)

Other members: Alvin AuYoung (UCSD), David C. Other members: Alvin AuYoung (UCSD), David C. Parkes (Harvard)Parkes (Harvard)

p2pecon’05

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Pitching markets to systems folksPitching markets to systems folks

““Markets don’t workMarkets don’t work””

……but they do provide but they do provide efficiencyefficiency

““Gaming isn’t importantGaming isn’t important””

……but it adds but it adds complexitycomplexity

Need more experimental dataNeed more experimental data

We We deployeddeployed a system and observed usage a system and observed usage

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Mirage testbedMirage testbed

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11710498 102

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101 12540 62 72

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4627

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150 nodes@ Intel

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Why testbedWhy testbed Many users from different projectsMany users from different projects

Diverse resource requirementsDiverse resource requirements

Valuation variesValuation varies

Resource contention can be seriousResource contention can be serious

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Initial approachInitial approach Greedy first-price combinatorial auction Greedy first-price combinatorial auction

Expressive language for space/timeExpressive language for space/time

Non-sealed and modifiable biddingNon-sealed and modifiable bidding

Virtual currency policyVirtual currency policy

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Bidding interfaceBidding interface

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Greedy combinatorial auctionGreedy combinatorial auction

1:00

3:00

2:00

4:00

5:00

v=27

v/nd = 3

v=12

v/nd=1.5

v=16

v/nd=2

v=6

v/nd=1

v: valuen: # nodesd: hours

node 1….

node 4

Rolling Window

available

sold

n=3

d=3

n=2n=4 n=3

d=4 d=2 d=2

Bids

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Greedy combinatorial auctionGreedy combinatorial auction

1:00

3:00

2:00

4:00

5:00

v/nd=3 v/nd=1.5v/nd=2 v/nd=1

X X X X2:

00

4:00

3:00

5:00

6:00

WINv: valuen: # nodesd: hours

node 1….

node 4

high low

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Virtual currency policyVirtual currency policy Users don’t contribute / pay to use MirageUsers don’t contribute / pay to use Mirage

User account:User account:

Baseline amount Baseline amount bb (e.g. 1,000 credits) (e.g. 1,000 credits)

Proportional-share Proportional-share ss (e.g. 5%) (e.g. 5%)

Revenue reallocation Revenue reallocation

Redistributed to Redistributed to allall accounts proportionally accounts proportionally

Savings tax (“use it or lose it”)Savings tax (“use it or lose it”)

Tax “wealthy” accounts and redistribute to “poor” onesTax “wealthy” accounts and redistribute to “poor” ones

“Markets don’t work”

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People do use Mirage…People do use Mirage…Node Hours (fraction)Node Hours (fraction) ProjectProject

113827 (36.7%)113827 (36.7%) distregdistreg

62015 (19.8%)62015 (19.8%) tinierdbtinierdb

34913 (11.2%)34913 (11.2%) snetroutingsnetrouting

26161 (8.4%)26161 (8.4%) bbqbbq

24831 (7.9%)24831 (7.9%) dcsdcs

14758 (4.7%)14758 (4.7%) rbroutingrbrouting

10940 (3.5%)10940 (3.5%) xmeshxmesh

10603 (3.4%)10603 (3.4%) radsrads

8124 (2.6%)8124 (2.6%) tinyostinyos

5464 (1.7%)5464 (1.7%) ucducd

512 (0.2%)512 (0.2%) nucleusnucleus

0 (0%)0 (0%) tinydbtinydb

0 (0%)0 (0%) racelabracelab

0 (0%)0 (0%) princetonprinceton

0 (0%)0 (0%) harvardharvard

0 (0%)0 (0%) fpsfps

0 (0%)0 (0%) epflepfl

0 (0%)0 (0%) bbq_routingbbq_routing

Over 300 bids,

300,000 node hours

over 4 months

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Resource contentionResource contention

SIGCOMM SenSys

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Wide range of valuationsWide range of valuations

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Increasing values during contentionIncreasing values during contention

SIGCOMM SenSys

“Gaming isn’t a problem”

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S1: UnderbiddingS1: Underbidding Cause: allowed bidders to see outstanding bidsCause: allowed bidders to see outstanding bids

During underutilization periods, During underutilization periods,

users bid less than users bid less than recentrecent value (e.g. 10,10,1) value (e.g. 10,10,1)

Result: lower efficiencyResult: lower efficiency

Counter: use sealed-bid auctionCounter: use sealed-bid auction

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S2: Iterative biddingS2: Iterative bidding Cause: allowed bidders to modify bid valuesCause: allowed bidders to modify bid values

Usability overhead mattersUsability overhead matters

Most modified once only, understatingMost modified once only, understating

Result: increased complexityResult: increased complexity

Counter: bid only once Counter: bid only once

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S3: Rolling window attackS3: Rolling window attack

v/nd = 2 v/nd = 1

X X WIN

v = 32 v = 16

v/nd = 1

v = 4 (T)

Bid Horizon: bids cannot start later then here

Xv/nd = 1

X

v = 8

X

Hmm...

v/nd = 1

v = 4 (T+1)

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S3: Rolling window attackS3: Rolling window attack

v/nd = 2 v/nd = 1

v = 32 v = 16

v/nd = 1

v = 8

X XWIN

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v/nd = 1.8

v = 29

v/nd = 4

v = 16

S4: Sandwich attackS4: Sandwich attack

v/nd = 3 v/nd = 2

X X

v = 48 v = 32

Hmm...

v/nd = 1

v = 12

WIN WIN

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ConclusionConclusion MarketsMarkets

Users seem to respond to markets approachUsers seem to respond to markets approach

Gaming Gaming

Users know what’s going onUsers know what’s going on

Hurts efficiency and adds complexityHurts efficiency and adds complexity

Deploying an online strategyproof mechanismDeploying an online strategyproof mechanism

We need more deploymentsWe need more deployments

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SitesSites MirageMirage

Google: “Mirage Intel Berkeley”Google: “Mirage Intel Berkeley”

http://mirage.berkeley.intel-research.comhttp://mirage.berkeley.intel-research.com

Other group papersOther group papers

http://www.chaki.comhttp://www.chaki.com