1Copyright2015EMCCorporation.
Allrightsreserved.
RAIDShield:Characterizing,Monitoring,andProactivelyProtectingAgainstDiskFailuresPresenter:AoMaAjointworkwithFredDouglis,GuanlinLu,DarrenSawyerSurendarChandra,WindsorHsu2Copyright2015EMCCorporation.
Allrightsreserved.
DiskfailuresarecommonplaceWhole-diskfailurePartialfailureRAIDiswidelydeployedProtectdataagainstfailureswithredundancyPervasiveRAIDProtection3Copyright2015EMCCorporation.
Allrightsreserved.
StoragesystemisevolvingEscalateduseoflessreliabledrivescausesmorewhole-diskfailuresIncreasingdiskcapacityresultsinmoresectorerrorsSolutionAddextraredundancy(RAID5,RAID6,…)–EnsuredatareliabilityatthecostofstorageefficiencyRAIDOverviewIsaddingextraredundancyanefficientsolution4Copyright2015EMCCorporation.
Allrightsreserved.
Analyzed1millionSATAdisksandrevealedFailuremodesdegradingRAIDreliabilityReallocatedsectorsreflectdiskreliabilitydeteriorationDiskfailureispredictableBuiltRAIDSHIELD,anactivedefensemechanismReconstructfailingdiskbeforeit'stoolate!
PLATE:single-diskproactiveprotection–Deploymenteliminates70%ofRAIDfailuresARMOR:diskgroupproactiveprotection–RecognizevulnerableRAIDgroupsWhatWeDid5Copyright2015EMCCorporation.
Allrightsreserved.
BackgroundDiskfailureanalysisRAIDSHIELD:IdentifyfailureindicatorReallocatedSector(RS)characterizationSinglediskproactiveprotectionDiskgroupproactiveprotection5Outline6Copyright2015EMCCorporation.
Allrightsreserved.
Diskfailuredoesnotfollowafail-stopmodelTheproductionsystemsstudieddefinefailureasConnectionislostAnoperationexceedsthetimeoutthresholdWritefailsWhole-diskFailureDefinition7Copyright2015EMCCorporation.
Allrightsreserved.
EachdiskdrivemodelisdenotedasRelativesizeswithinafamilyareorderedbythecapacitynumber–E.
g.
A-2islargerthanA-1DiskModelPopulation(Thousands)FirstDeploymentLogLength(Months)A-13406/200860A-216511/200860B-110006/200848C-19310/201036C-225312/201036D-138409/201121DiskDataCollection8Copyright2015EMCCorporation.
Allrightsreserved.
WhatDoRealDiskFailuresLookLike9Copyright2015EMCCorporation.
Allrightsreserved.
0001424462031010203040500-612-1824-3036-4248-54A-2MonthDistributionofLifetimeofFailedDrives001241534291130102030400-612-1824-3036-4248-54A-1MonthAlargefractionoffaileddrivesarefoundatasimilaragePercentage(%)Percentage(%)10Copyright2015EMCCorporation.
Allrightsreserved.
ThenumberofaffecteddiskskeepgrowingAbout10%ofdisksgetsectorerrorsatthe3rdyearSectorerrornumbersincreasescontinuouslyAverageerrorcountincreases25%to300%yearoveryearIncreasingFrequencyofSectorErrors11Copyright2015EMCCorporation.
Allrightsreserved.
DrivefailingatasimilarageFailurerateisnotconstantAhighriskofmultiplesimultaneousfailuresIncreasingfrequencyofsectorerrorsExacerbateriskofreconstructionfailuresPassiveRedundancyisInefficientEnsuringreliabilityintheworstcaserequiresaddingconsiderableextraredundancy,makingitunattractivefromacostperspective12Copyright2015EMCCorporation.
Allrightsreserved.
MotivationEnsuredatasafetywithminimalredundancyProactivelyrecognizeimpendingfailuresandmigratevulnerabledatainadvanceMethodologyIdentifyindicatorofimpendingfailureIndicatorcharacterizationProactiveprotectionRAIDSHIELD,TheProactiveProtection13Copyright2015EMCCorporation.
Allrightsreserved.
PotentialindicatorsVariousdiskerrorsCriteriaofagoodindicatorIthappensmuchmorefrequentlyonfaileddisksratherthanworkingdisksApproachQuantifythediscriminationbetweenerrorvalueonfaileddisksandworkingones–DecilescomparisonisusedIdentifyFailureIndicator14Copyright2015EMCCorporation.
Allrightsreserved.
FaileddiskshavemoremediaerrorsthanworkingonesThediscriminationisnotsignificantenoughMediaErrorComparison2359152232478611123471330020406080100123456789faileddiskworkingdiskDecilesA-2MediaErrorCount15Copyright2015EMCCorporation.
Allrightsreserved.
2238718732752281212422025000001262905001000150020002500123456789faileddiskworkingdiskA-2DecilesReallocatedSectorCountA-2DecilesRSisstronglycorrelatedwithdiskfailuresReallocatedSector(RS)Comparison16Copyright2015EMCCorporation.
Allrightsreserved.
MostfaileddrivestendtohavealargernumberofRSthanworkingonesRSisstronglycorrelatedwithwhole-diskfailures,followedbymediaerrors,pendingsectorerrorsanduncorrectablesectorerrorsCorrelationBetweenSectorErrorsAndWhole-diskFailureRSisastrongindicatorofimpendingdiskfailure17Copyright2015EMCCorporation.
Allrightsreserved.
LargerRScountimplieshigherfailurerateintwo-monthwindowDiskFailureRateGivenDifferentRSCount1.
767758083858689909091929393949502040608010004080120160200240280320360400440480520560600DiskFailureRate(%)RScountA-2RSCharacterization(1)18Copyright2015EMCCorporation.
Allrightsreserved.
LargerRScount,fastertofail10%25%median75%90%RSCountTimeMargin(Days)DiskFailureTimeGivenDifferentRSCountRSCharacterization(2)19Copyright2015EMCCorporation.
Allrightsreserved.
RScountindicatesthedegreeofdiskreliabilitydeteriorationUsetheRScounttopredictimpendingdiskfailureinadvancePLATE:SingleDiskProactiveProtection20Copyright2015EMCCorporation.
Allrightsreserved.
70.
166.
66461.
859.
952.
14742.
63936.
94.
52.
82.
11.
71.
40.
80.
70.
40.
30.
27010203040506070809010020406080100200300400500600failurespredictedfalsepositivePercentage(%)BoththepredictedfailureandfalsepositiveratesdecreaseasthethresholdincreasesSimulationResult:FailuresCapturedRateGivenDifferentRSThresholdRSthreshold21Copyright2015EMCCorporation.
Allrightsreserved.
551515801070020406080100WithoutProactiveProtectionWithProactiveProtectionHardwareFailuresOthersTripleFailuresEliminatedTripleFailuresSingleproactiveprotectionreducesabout70%ofRAIDfailures,equivalentto88%ofthetriple-diskfailuresPLATEDeploymentResult:CausesofRecoveryIncidentsPercentage(%)22Copyright2015EMCCorporation.
Allrightsreserved.
10%remainingtriplefailuresPLATEmissesRAIDfailurescausedbymultiplelessreliabledrives,whoseRScountshaven'texceedthethresholdTriagePrioritizediskgroupswithhighestriskMotivationofARMOR:TheRAIDGroupProactiveProtection23Copyright2015EMCCorporation.
Allrightsreserved.
1-11-21-31-42-12-22-32-43-13-23-33-44-14-24-34-4XXXXThreatofFailureImminentFailureGoodDiskHealthyDG1ImminentFailureofDG2ProtectedDG3PossibleFailureofDG4Singlediskprotection:Replace2-3,2-4,3-4(PLATE)Can'tidentifyDG4northedifferencebetweenDG2andDG3Groupprotection:ReplaceDG4orincreaseredundancy(ARMOR)ProtectDG4andrecognizethedifferencebetweenDG2andDG3DiskGroupProtectionExample24Copyright2015EMCCorporation.
Allrightsreserved.
CalculatethesinglediskfailureprobabilityConditionalprobabilitythroughBayesTheoremCalculatetheprobabilityofavulnerableRAIDCombinationofthosesinglediskprobabilitiesthroughjointprobabilityARMORMethodology25Copyright2015EMCCorporation.
Allrightsreserved.
ThediscriminationshowsARMORiseffectivetorecognizeendangeredDGsInpractice,itidentifiesmostDGfailuresthatarenotpredictedbyPLATEProbabilityDecilesdistributionEvaluation0.
250.
330.
390.
440.
460.
50.
630.
730.
930.
150.
20.
230.
250.
270.
280.
30.
310.
3200.
20.
40.
60.
81123456789GroupswithmorethanonefailureGroupswithoutfailure26Copyright2015EMCCorporation.
Allrightsreserved.
GooglereportsSMARTmetricssuchasreallocatedsectorstronglysuggestanimpendingfailure,buttheyalsodeterminethathalfofthefaileddisksshownosucherrors[Pinheiro'07]DifferentworkloadandRAIDrewriteDiskfailurepredictionAveragemaximumlatency[Goldszmidt'12]SMARTfailureprediction[Murray'05,Hughes'02]RelatedWork27Copyright2015EMCCorporation.
Allrightsreserved.
Weanalyzed1millionSATAdrivesObservefailuremodesdegradingRAIDreliabilityRevealRScountreflectsthediskreliabilitydeteriorationDiskfailureispredictableWebuiltRAIDSHIELD,anactivedefensemechanismPLATE:singlediskproactiveprotection–Deploymenteliminates70%ofRAIDfailuresARMOR:diskgroupproactiveprotection–RecognizevulnerableRAIDgroups–HopetodeployinfutureIsaddingextraredundancyanefficientsolutionUseasmuchredundancyasneededtoensureavailabilityProactivereplacementshoulddecreasethelevelneededSummary28Copyright2015EMCCorporation.
Allrightsreserved.
RAIDShield:Characterizing,Monitoring,andProactivelyProtectingAgainstDiskFailuresQuestionsAcknowledgementAndreaArpaci-DusseauandRemziArpaci-DusseauDataDomainengineerteam,membersofADandCTOoffice,StephenManley29Copyright2015EMCCorporation.
Allrightsreserved.
CalculatethesinglediskfailureprobabilityCalculatetheprobabilityofavulnerableRAID
青果网络QG.NET定位为高效多云管理服务商,已拥有工信部颁发的全网云计算/CDN/IDC/ISP/IP-VPN等多项资质,是CNNIC/APNIC联盟的成员之一,2019年荣获国家高薪技术企业、福建省省级高新技术企业双项荣誉。那么青果网络作为国内主流的IDC厂商之一,那么其旗下美国洛杉矶CN2 GIA线路云服务器到底怎么样?官方网站:https://www.qg.net/CPU内存系统盘流量宽带...
Hostadvice主机目录对我们的服务进行了测试,然后给PQ.hosting颁发了十大WordPress托管奖。为此,宣布PQ.Hosting将在一周内进行折扣优惠,购买和续订虚拟服务器使用优惠码:Hostadvice ,全部优惠10%。PQ.hosting,国外商家,成天于2019年,正规公司,是全球互联网注册商协会 RIPE 的成员。主要是因为提供1Gbps带宽、不限流量的基于KVM虚拟的V...
RFCHOST,这个服务商我们可能有一些朋友知道的。不要看官网是英文就以为是老外服务商,实际上这个服务商公司在上海。我们实际上看到的很多商家,有的是繁体,有的是英文,实际上很多都是我们国人朋友做的,有的甚至还做好几个品牌域名,实际上都是一个公司。对于RFCHOST商家还是第一次分享他们家的信息,公司成立大约2015年左右。目前RFCHOST洛杉矶机房VPS正进行优惠促销,采用CN2优化线路,电信双...
阵列卡为你推荐
公司网络被攻击网络遭受攻击分为哪几类老虎数码相机里的传感器CCD和CMO是什么意思?www.7160.com电影网站有那些嘀动网在炫动网买鞋怎么样,是真的吗蒋存祺蒋存祺的主要事迹51sese.com谁有免费电影网站baqizi.cc孔融弑母是真的吗?javlibrary.comSSPD-103的AV女主角是谁啊1!!!!求解www.k8k8.com谁能给我几个街污网站我去自己学月风随笔关于中秋作文
私人服务器 10t等于多少g godaddy web服务器架设软件 什么是刀片服务器 国外免费全能空间 hkg 刀片式服务器 135邮箱 1g空间 paypal注册教程 爱奇艺会员免费试用 免费外链相册 河南移动梦网 电信网络测速器 贵阳电信测速 免费蓝钻 脚本大全 服务器机柜 服务器操作系统 更多