6.888 lecture 6: network performance isolaon · 6.888 lecture 6: network performance isolaon...

6.888Lecture6:

NetworkPerformanceIsola8on

MohammadAlizadeh

Spring2016

1

Mul8-tenantCloudDataCenters

Sharedinfrastructurebetweenmul8pletenants/apps

LackofPerformancePredictability

Unpredictableperformance,esp.atthetail

GAE memcache read 100 values

3

Conges8onKillsPredictability

4Apr2013 4NSDI2013

SharingtheNetwork

6

Alice’sSwitch

VM1 VM2 VMnVM3…

Bob’sSwitch

VM1 VM2 VMiVM3…

CustomerspecifiescapacityofthevirtualNIC.Notrafficmatrix.

…

…HoseModel

(Duffieldetal.,SIGCOMM’99)

2GhzVCPU15GBmemory1Gb/snetwork

SharingtheNetwork

Tenantselectsbandwidthguarantees.Models:Hose,VOC,TAG

PlaceVMs,ensuringallguaranteescanbemet

Enforcebandwidthguarantees&Providework-conserva8on

VMsetup

Run8me

Oktopus[SIGCOMM’10]Hadrian[NSDI’13]CloudMirror[SIGCOMM’14]

Seawall[NSDI’10]FairCloud[SIGCOMM’12]EyeQ[NSDI’13]Elas8cSwitch[SIGCOMM’13]

….²  AdaptedfromslidebyLucianPopa

ExampleRun8meSystem:EyeQ(NSDI’13)

8

Shim

Shim

Shim

Shim

DistributedRateAlloca8on

VM

VMVM

VM

VM

VM

2Gb/s

8Gb/s

2Gb/s

2Gb/s

8Gb/s 8Gb/sShim

10Gb/spipe(min)RateGuarantees

EyeQShimLayerInthetrusted

Domain(Hypervisor/NIC)


VM

VMVM

VM

VM

VM

2Gb/s

8Gb/s

2Gb/s

2Gb/s

8Gb/s 8Gb/s

5Gb/s

5Gb/s

10Gb/spipe(min)RateGuarantees

RXModule


VM

VMVM

VM

VM

VM

2Gb/s

8Gb/s

2Gb/s

2Gb/s

8Gb/s 8Gb/s

5Gb/s

5Gb/s


VM

VMVM

VM

VM

VM

2Gb/s

8Gb/s

2Gb/s

2Gb/s

8Gb/s 8Gb/s

1Gb/s

1Gb/s

8Gb/s

VM

VMVM

VM

VM

VM

2Gb/s

8Gb/s

2Gb/s

2Gb/s

8Gb/s 8Gb/s

1Gb/s

1Gb/s

8Gb/s

5Gb/s


RXModule


VM

VMVM

VM

VM

VM

2Gb/s

8Gb/s

2Gb/s

2Gb/s

8Gb/s 8Gb/s

1Gb/s

1Gb/s

5Gb/s

5Gb/s

Sparecapacity


VM

VMVM

VM

VM

VM

2Gb/s

8Gb/s

2Gb/s

2Gb/s

8Gb/s 8Gb/s

2.5Gb/s

2.5Gb/s

5Gb/s

5Gb/s

Transmit/ReceiveModules

VM

VMVM

VM

VM

VM

2Gb/s

2Gb/s

8Gb/s 8Gb/s

1Gb/s

1Gb/s

Conges8ondetectorsRatelimit.

Ratelimit.

Ratelimit.

RCP:Ratefeedback(R)every10kB(noper-sourcestateneeded)

Per-des8na8onratelimiters:onlyifdest.iscongested…bypassotherwise

FeedbackpktRate:1Gb/s 2Gb/s

8Gb/s

SharingtheNetwork

Tenantselectsbandwidthguarantees.Models:Hose,VOC,TAG

PlaceVMs,ensuringallguaranteescanbemet

Enforcebandwidthguarantees&Providework-conserva8on

VMsetup

Run8me

²  AdaptedfromslidebyLucianPopa

CloudMirror

UsesElas8cSwitch[SIGCOMM’13]

CloudMirror

18

² Slidesbasedonpresenta8onbyJKLee(HP)

Mo8va8on

Cloudapplica8onsarediverse&complex

Bandwidthmodelslikepipeandhosenotagoodfit

19[Bing.com traffic pattern, Sigcomm’12]

web

DB

cache

web

logic

Hosemodelisunfit

HoseaggregatesBWtowardsdifferentcomponents

–  Toocoarse-grained–  Preventsaccurateandefficientguaranteesoninfrastructure

intra-component (self-edge) inter-component

Hoseistoocoarse-grained

web logic DB

Web

… …

Logic DB

400 100

300

200

500

800

TCP-like fair allocation would yield 300:200

3-tier web example Hose model

congestion

w w

2B

web (N)

B

… L L

… D D …

logic (N) DB (N)

2B

Hoseover-provisionsphysicallinkbandwidth

Hosemodelreserva8onatL2:2B·N

N: # VMs in each tier B: per-VM per-edge bandwidth

Physical deployment example

2X overprovision by Hose Model

2 B N

logic - DB demand = B · N

web (N)

logic (N)

DB (N)

B B

B

web + logic DB

L1 L2

w w …

L L …

D D …

Contribu8ons

1.  TenantApplica8onGraph(TAG)-  Accurateforcomplexapps-  Flexibletoelas8cscaling-  Intui8ve

2.  VMPlacementAlgorithm-  Guaranteebandwidthandhighavailability-  Efficientfornetworkandcomputeresources

23

TenantApplica8onGraph(TAG)1.Aggregatepipes(likeHose)-  Modelsimplicity-  Mul8plexinggain

2.Preserveinter-componentstructure(likePipe)-  Accuratelycaptureapplica8ondemands-  Efficientlyu8lizenetworkresources

DB

mem

web

logic

DB

mem

web

logic

DB

mem

web

logic

Component-level graph

TenantApplica8onGraph(TAG)

web(Nw)

DB(ND)

BsndBrcv

Bin

web

DB

BsndBrcv

TAG model

Bsnd=per-VMsendingbandwidth(VM-to-componentaggrega8on)Brcv=per-VMreceivingbandwidth(component-to-VMaggrega8on)

Whatdoself-edgesmean?

AbstractmodelsinTAGSelf-edge↔HoseDirec8onaledge↔direc8onalHose,VirtualTrunk

Total guarantee of virtual trunk = min(Bsnd·Nw, Brcv·ND)

Brcv

web(Nw)

Bsnd

… …

DB(ND)

Bin

Virtual Switch Virtual Trunk

web (Nw)

DB (ND)

Bsnd Brcv

Bin

TAG model

Ques8ons

HowareTAGsconstructed?Howtopredictbandwidthdemands?WhatismissingfortheTAGmodel?

CloudMirroropera8on

VM placement BW reservation

Admission control

TAG spec Network topology & BW reservation state

Available VM slots

host1 10 host2 50 host3 25

Web (N)

DB (N)

B B

Discussion

29

NextTime:CentralizedArbitra8on

30

6.888 lecture 6: network performance isolaon · 6.888 lecture 6: network performance isolaon...

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