A to So Rig in Mainframes in Perspective Whitepaper 2

8/2/2019 A to So Rig in Mainframes in Perspective Whitepaper 2

1/20

White paper

The slumbering dinosaur awakes


2/20

CONTENTS

INTRODUCTIONANDSUMMARY 3

HOWWEGOTHERE:THEROADLESSTRAVELLED 5

2.1 Marketposition 5

2.2 Availability,perormanceandutilisation 6

2.3 Sotwareandstandards 7

2.4 Costoownershiporusage 8

2.5 Theevolutionocomputing 8

3 HOWDOESMAINFRAMEFITWITHINCURRENTIT? 9

3.1 Marketposition 9

3.2 Availability,perormanceandutilisation 9

3.3 Sotwareandstandards 10

3.4 Costoownershiporusage 11

3.5 Mainramesandutilitycomputing 12

4 NEWDEVELOPMENTSWITHINTHEMAINFRAMEWORLD 13

4.1 TheIBMMainrameCharter 13 4.2 Specialityengines 13

4.3 OpenSource 14

4.4 ServiceOrientedArchitecture(SOA) 14

4.5 Greyingotheworkorce 15

5 THEMAINFRAMEBUSINESSCASE 16

6 COLOPHON 19

6.1 Reerences 19

6.2 Acknowledgements,etc. 19


3/20

3

INTrOduCTION

aNd Summary

Inspiteocontinualrumoursotheirdeath,mainramesarealiveandwell,andrepresentavery

viableandcost-eectiveplatormorrunningmodernITsystems.Thismaycomeasasurpriseto

some,especiallythosewhomovedotheplatormadecadeormoreago.

IntheiruseoIT,businesseshavetomakeacontinuousbalancebetweenqualityoservice(QoS)

andcost.

Qualityoservice:

> Improvedavailabilityoservices

> Reducedtime-to-marketornewservices

> Reducedcomplexity,easeouse

> Compliancetoregulations

Cost:

> Reducedpurchaseandrunningcosts

> Increasedresourceutilisation

> Reducedadministrativeoverhead

> Contracttransparency

Someashionsseemtorunincirclesandcomebacktohauntus.Forsomeous,itmayseem

tobesowithmainrames:weallusedtousethemyearsago,butthenmostorganisationsdrited

oontootherplatormsastheydownsized.Nowthosepeoplearebusyre-centralising,andmany

areremindedohowthingsusedtobeonthemainrame.

mainframe1

n.1.Anobsoletedevicestillusedbythousandsoobsoletecompaniesservingbillionso

obsoletecustomersandmakinghugeobsoleteproftsortheirobsoleteshareholders.

Andthisyearsruntwiceasastaslastyears.n.2.AlargePCperipheral

Butitwouldbeamistaketothinkthatthosepeoplewillndthemainrameplatormexactlyas

theyletityearsago.Themainramehasnotstoodstillinthattime,buthasevolvedalongside

otherplatorms,whilestillretainingthelevelsoqualityandreliabilityitalwayshad,andthegrowth

inmainramesalesissteady.

Mainrames,asthebigironothecomputingworld,arereliedonbymanylargebusinessesto:> Perormthousandsotransactionspersecond;

> Supportthousandsoconcurrentusers,allaccessingthesamesystemsandresources;

> Allowmultipleapplicationprogramstoaccessnumerousresourcessaelyandsecurely;

> Manageenormousvolumesostoreddata;

> Transervastquantitiesodatainandoutothesystem.

Themainrameplatormhasareputationoritsextremelyhighleveloqualitybut,amongstthose

whodonotusethem,orbeingexpensive,monolithicandinfexible.Yetitcanbeverycost-eec-

tivecomparedtoaprolierationosmallersystems,canbefexiblyconguredandre-congured.

Itisactuallyaconstantly-evolvingplatorm.

Recentstudies,undertakenbyIBMthemselvesbutendorsedbyIlluminata,showaverypositivecostcomparisonorthemainrameagainstotherplatorms.

1TheDevilsITDictionary, IshamResearch,www.isham-research.co.uk


4/20

4

Therearealsoconcernsaboutitbeinganislandocomputing.IntherstyearsoitslieIBM

indeedinventeditsowndeactostandards,butarguablyhadnooptiontodootherwise,and

sincethenithasbeenbusysupportingindustryanddejurestandards;thesedaysitisextremely

well-connectedtootherplatormsAnd,orthebestobothworlds,themainramewillhappilyrun

veryoldsystemsontheoldstandardsalongsidenewonesbuilttomodernstandards.

Thereisurtherironyinanyresistancetotheuseomainrames,becauseeveryoneinITistalking

aboutvirtualisationandutilitycomputing(seeIntroducingUtilityComputing,AtosOrigin,October

2006).Butbothconceptshavebeenaroundinthemainrameworldor30yearsormore.By

providingvirtualisation,VMwareisdoingorIntelplatormswhatVM/370didonmainramesinthe

1970s.Mainrameisautilityservice,andhasalmostalwaysbeenso.Manyadvocatesoutility

servicesareactuallyreinventingthemainrameinmanyaspectsowhattheyseektoachieve.

So,themainramestyleocomputingstillhasaroleorthosewhosebusinessesaredependent

onhigh-qualitycomputingenvironments,sowhatbetterplatormtosupplythisneedthanthe

mainrameitsel?

Thispaperseekstoexplainthisapparentconundrumandtogivesomeoutlineastohowthe

mainrameplatormcanbestbestrategicallyconsidered.


5/20

5

HOw wE gOT HErE:

THE rOad lESS TravEllEd

Tworoadsdivergedinawood,andI

Itooktheonelesstravelledby,

Andthathasmadeallthedierence.

TheRoadNotTaken,RobertFrost(18741963)

.MARkETPOSITION

In1943,ThomasWatsonoIBMhadamouslysaid,I

thinkthereisaworldmarketormaybevecomputers.

Butoverthenexttwodecadesamarketdidindeed

ariseoraewmoresystemsthanthat.Inthe1960s

and70stherewereanumberosuppliersolarge-scale

computers,knowncolloquiallyasIBMandtheseven

dwarves:Burroughs,ControlData,GeneralElectric,

Honeywell,NCR,RCAandUnivac.

TheintroductionbyIBMotheSystem/360in1964

wasarevolution,mainlybecauseothenatureothe

architecture.Beorethen,eachcomputerproduced

wasauniquesystem,madetoacustomersorder,

withnocontinuityindesign.Andeachwas,essentially,

asingle-applicationsystem,withdierentsystemsoreithercommercialorscienticworkloads.

TheSystem/360wasaamilyooriginallyvemachines,

sharingcommonarchitectureandperipherals.Cus-

tomerscouldupgradetonewerandlargerprocessors

withoutconcernastoproblemsocompatibility.

TheSystem/360architecturedesignbriewastoulla

numberokeyrequirements:

> Handleverylargeamountsofexibly-managed

storage,withavarietyodataormats;

> Highinputandoutput(I/O)rateswithstandardinteraces;

> General-purposeprocessingcapability,

withcontrolledsupervisorunctions;

> Scalability,withaninitialrangeoonetoty.

TheS/360wastherstsystemtousemicrocode(or

rmware),ratherthanhavealloitsunctionalityhard-

wired.Thesestoredmicro-instructions,notaccessible

tonormalprogramsotherthantoexecutethem,provide

alevelofexibilitybetweenthehardwareandsotware:

iasystemneedstobecorrectedorextended,that

upgradecantakeplacewithoutreplacingthesystemhardwareitsel.Thestandardarchitecturalinterace

wasdescribedinadocumentcalledthePrincipleso

Operation.

Suchanarchitecturealsomeantthatothersuppliers

(e.g.Amdahl,StorageTek,Hitachi)couldbuildhardware,

whetherprocessorsorstorage,thatwouldsitalong-

sidethatoIBMandbeindistinguishabletothesys-

temssotware,theapplicationsandtoendusers.This

developmentopenedupthemainramemarkettoprice

competition.

Evenbythe1970s,withthegrowthinsupplyoptions,

computerswerestilllargeandexpensivecentralised

resources,involvingmajorcapitalinvestmentsandwith

teamsosupportspecialists,usedbylargecompanies

suchasbanksorbulkdataprocessing.Bythattime,

thecompetitiontoIBMhadbecomeTheBunch:Bur-

roughs,Univac,NCR,CDCandHoneywell,withother

localmanuacturersinEurope.

Themarketsueredurthershake-outandtake-overs

inthe1980s.Bytheearly1990salmosteveryonehad

decidedthatthemarketorthemainramewasdying,

asmoreandmorecustomersdown-sizedtoother

platorms.

Ironically,asaback-ocesystem,themainrame

marketwasrevivedinthe1990s.Thiswaspartlyby

theopeningupotheplatormtoindustrystandards,

andpartlybytheadventoe-businessandtheuseo

theinternetorcommercialactivities.Thenumbero

back-ocetransactionsandthesizeandactivitylevelo

databasesgrewenormously,generatingarevivalinthe

market.Thesesystemssoonbecametoobigandcriti-

caloramigrationtoanyotherplatormtobeconsid-

ered,orevenpossible.

IBM370/165inEindhovenin1974


6/20

6

. AVAILABILITY,PERFORMANCEANDUTILISATION

Theactorsoavailability,perormanceandutilisationare

essentiallywhatdeterminewhatisandisnotamain-

rame.Mainramesarebuilttoaleveloquality.From

theoutset,thedesignoamainramewasthatitcan

runmultipleworkloadsinthesamesystemenvironment

inthesamemachine.Theemphasisinthemainrame

worldwasonimprovingReliability,AvailabilityandSer-

viceability(RAS,asIBMcalledit).Internalsecurityand

integritywasbuiltintotheoriginalS/360hardwarearchi-

tecture,withprovisionoraprotectedlevelosupervisor

modecontainingsysteminstructionsoruseonlybythe

operatingsystem.

Thiscontinuedwiththeadventinthe1970sotherst

MVSoperatingsystem,inwhichsystemintegritywas

paramountandwhichcompletelyisolatedanyone

workloadromanotherrunningonthesamemachine.

Itmadeveryecientuseo(thenscarceandexpensive)

realmemoryresourcesbysharingthem,anddoingso

verysecurely,bytheuseovirtualmemory,usingdy-namicaddresstranslation(DAT)andhardwarestorage

keys.Thissecuritywithinthesystemwaslaterextended

tooutsideresourcessuchasstoragebythesecurity

system,RACF,usingwhichtheworkloadsandtheir

datacouldbesecuredandcompletelyisolated.

Theworkloadswithinamainrameenvironmentcould

begiventheappropriatepriorityviaaworkloadsched-

uleranddispatcher.Themachinecanbeloadedupto

100%withoutperormanceissues;asustainedpeak

loaddoesnotcausemajorperormanceissues.

Availabilitywasalreadyhighbutbecamehigherinthe

mid1990swiththeadditionoParallelSysplex,oneo

therstclusteringtechniqueswhereyoucouldcouple

32mainramesactingasonemachine.Theconceptis

similartoUnixclustering,exceptsystemscanbeadded

orremovedasneededwhileapplicationscontinueto

processuninterrupted.ParallelSysplexallowedcon-

currentdataaccessromanynodewithoutimpacting

perormanceorintegrity.Workloadscanbeclonedand

distributedacrossthecluster,whichcanbespreadup

toadistanceo10kmcablelength.Youcouldputone

haloyourserversinonelocationandtheotherhal

inanotherlocationatadistanceoupto10km,with

themstillactingasonemachineinthetwindatacentre

complex.ThisisextendedbyGeographicallyDispersed

ParallelSysplex(GDPS),whichinspiteothenameis

notactuallyParallelSysplex,whichcannotworkover

thelongerdistancesinvolved.ButGDPSisawayto

provideautomateddisasterrecoveryovergreaterdis-

tances,whichcanbeover100km.Itdoesdependon

usingtherightmixoIBMhardwareandsotware.

Virtualizationwasintroducedin1972withtheVMoperatingsystem.WiththeadventoLogicalPartitions

(LPARs)intheearly1980scamehardwareservervir-

tualization,wherethehypervisorkernelwasbuiltinto

thesystemsmicrocode.Logicalpartitions(LPARs)can

becreatedtoruncompletelyindependentworkloads

underseparateoperatingsystemsonthesameproces-

sorcomplex.Thevirtualizationisnotonlyoractionso

servercapacitybutalsoomemoryandI/Ochannels.

Sincetheearly1990staperobotshavebeencongu-

rableasVirtualTapeServers.


7/20

Virtualisation is the creation of a logical abstraction of the physical environment. It involves the de-coupling of an interface, so that different and

variable resources can be used beneath the surface. It can make many appear as one, or one appear as many.

Virtualisation can be applied to a myriad of resources, examples of which include:

> Services: de-coupling what is used from the infrastructure used to provide it;

> Applications: using Web Services interfaces, so that multiple customers can make use of a single application process;

> Servers: running multiple applications on the same box, whether in the same or using multiple operating systems;

> Storage: allowing data to be stored across a range of physical storage devices;

> Networks: both wide-area (WAN) and local (LAN): running different services over the same cables.

Virtualization can be made to work across an increasingly heterogeneous range of devices, so that devices of different types can be combined

and replaced. Virtualisation allows increased utilisation of these resources.

.3SOFTWAREANDSTANDARDS

Mainramesretaintheircontinuitylargelybecause,

althoughallothecomponentsmaychange,theymain-

tainstrictbackwardcompatibilityoroldsotware.New

versionsextendacilitiesratherthanchangethem,and

no-onehastoundertakeaorcedmigrationorre-write

becauseanewversionothehardwareorsotware

emerges.

Multipleoperatingsystemscanberunonthemainrame:

> z/OS:thefagshipoperatingsystemorhigh-availabil-

ityandhigh-loadworkloads,evolvedromMVT,MVS,OS390;

> zVM:ahypervisor,allowingmultipleoperating

systemstoberunwithinonecomplex,evolvedrom

VM/370;

> zVSE:asmalleroperatingsystem,originallyor

lower-endsystems,evolvedromDOS,DOS/VSE;

> zLinux:aullLinuximplementation,availableaseither

SUSEorRedhatdistributions;

> TPF:areal-timeandlarge-scaletransactionenviron-

ment,developedasaspecialOSorairlines.

TheycanallberuninanLPAR,undercontroloahardwarehypervisor,orunderzVM.Inz/OSyoucanrun

Unixprograms,becauseitcontainsaPOSIX-standard

Unixunderitshood.

Middlewarerstaroseinthemainrameworldasalayerosotwareabovetheoperatingsystemtoacilitate

buildingandrunningapplications.Withintheoperating

systemyouhavethechoiceoanumberomiddleware

environments:

> databasemanagementsystems(DB2,IMS,IDMS,

Oracle,mySQL,Adabas);

> transactionprocessingsystems(CICS,IMS,TSO);

> batch;

> third-generationlanguages(goodoldCOBOL,

Fortran,PL/1,Pascal,C,Assembler,JAVA);

> ourth-generationlanguages(4GLs:Focus,Natural,

Mark-IV);> webhosting(Websphere,Apache,Weblogic);

> ISVo-the-shelapplications(SAP,etc.).

Thevastmajorityomainrameprogramsarestillthose

writteninCobol,withasignicantuseoPL/1,Assem-

bler,CandC++.Growingproportionsarenowbeing

writteninJava,especiallywiththegrowthinSOAand

WebServices.

Thereisalargeandmaturesetosystemmanagement

toolingtoautomateoperations,schedulers,security

management,tape-anddatamanagement.


8/20

.4COSTOFOWNERSHIPORUSAGE

Becauseoitsinnatescale,themainramehasnever

beencheaptoown,buttohelpcompensateorthatit

canbeveryhighlyutilisedandthevariousworkloads

canberunalongsideeachotherwithcompleteintegrity

andsecurity.Soitisveryappropriatetoshareamain-

ramebetweenmultiplecustomers,makingthecosto

usagemoreacceptable.

.5THEEVOLUTIONOFCOMPUTING

Computinghasevolvedinanumberowaves,each

seenasanewparadigmandaradicalimprovement

onwhatwentbeore:

Ratherthanbeingremainingstuckbehindintheoriginal

model,mainrameprocessinghasactuallyriddenmany

othesewaves.Indeed,withinanup-to-datemain-

rameenvironment,itispossibletoimplementthebest

aspectsoeachothesemodelsocomputing.

Themainramearchitecture,whileretainingcompatibility

throughout,hasitselevolvedoverthedecades:

> System/360in1964:theoriginalintroduction;

> System/370in1970:addingmulti-processing,

moreinstructionsandvirtualmemory;

> S/370-XA(eXtendedArchitecture)in1983:bringing

31-bitaddressing;

> ESA/390(EnterpriseSystemsArchitecture)in1990:

supportingtheuseomultipleaddressspaces;

> z/Architecturein2000:bringing64-bitaddressing

anddynamicchannels.

More choice,

lower IT and

business cost

Improve usability,

lower business cost

Increase manageability,

lower IT cost

Enhance exibility

Utility Computing

> Server-centric

> Computing on demand

> IT as utility

> still evolving

Distributed Computing

> Client/Server

> Fat clients: unlocked, then locked

> Ease o use, customisable

> Heterogeneous, difcult to manage

Enterprise portals

> Server-centric

> Central control and management

> Flexible use, customisable

> User-oriented

Server-based Computing

> Server-centric

> Central control and management

> Thin or at clients

> Application-oriented, exible use

Central Computing

> Server-centric

> Mainrames and dumb terminals

> Central control and management> Inexible use


9/20

Rumoursomydeathhavebeengreatlyexaggerated,

MarkTwain

Whyisthemainramestillbeingbuiltandused?They

continuetoprovidetheabilitytorundatabase,ap-

plication,leserver,webserver,rewall,etc.allonone

machine,anddosoataveryhighleveloreliability.

Inact,thegreatestlong-termthreattothemainrame

marketcomesnotromanyweaknessintheplatormit-

sel,butromthecontinuedevolutionootherplatorms

toalevelthatisgoodenoughtoreplaceit.

3.MARkETPOSITION

TherearestillplatormsotherthantheIBMzSeries

whicharesometimesdescribedasmainrames:Unisys

manuacturesClearPathsystemsandtheirES7000is

sometimesdescribedasanIntelmainrame.HPsells

theex-TandemNonStopsystems,andGroupeBullthe

DPSsystem.Whilstthesedohavesomecharacteris-

ticsincommonsuchasdesigned-inhighavailability

throughredundancytheIBMzSerieshaswellover90%omarketshareinthiseld:itisthemainrame.

UsageozSeriesmachines,asmeasuredbylicensed

processorusage,iscurrentlygrowingbyaround40%

perannum,accordingtoBloorResearch.Andmost

mainrameuserswillcontinuetogrowtheirinstalled

MIPSatacompoundannualgrowthrate(CAGR)o

between15%and20%,accordingtoGartner.

Thisseemstoarisebecausethoseorwhomthe

mainramewasnotsuitablehavealreadymovedothe

platorm,andthosewhoremainarestillgrowingtheus-agealongwiththeirbusiness.

IBMsrevenuesrommainramehardwarealoneare

around$4.3Bnperyear,towhichsotwareandser-

vicescanbeadded.Thoserevenueshaveremained

approximatelylevelinrecentyearswhilethenumbero

processorMIPSshippedhasincreasedmaniold,sug-

gestingthatthepriceperMIPShasdroppedsignicant-

lyoverthatperiod.

HOw dOES maINframE fIT

wITHIN CurrENT IT?

3. AVAILABILITY,PERFORMANCEANDUTILISATION

Mainramesprovideveryhighlevelsoavailabilityand

aulttolerance,andaredesignednottohavesingle

pointsoailure.Morethananyothersizeableplatorm,

thesesystemshaveredundantinternalcomponents

andengineering:IBMz9serversexecuteeveryinstruc-

tiontwice,inparallel,andcomparetheresults(lock-

stepping).Workloadcanbeshitedin-fighttospare

processors,withoutimpactingtherunningsystems.

Indayswhenmanysupplierstalkintermsove

9savailability2,itissalutarytorecognisethatmost

mainramesalreadycurrentlydeliver100%availability

(althoughservicehoursmaybelessthanthatgure).

Theydosowithhighlevelsoperormance(thereis

typicallynolowQoSoptionwithmainrameservices)

andwithaMTBFoover20years.Indeed,thereseems

tobesomedebateintheindustryastotheMeanTime

2Readersshouldalwaysbewaryoeasyclaimsohighlevelsoavailability.

Costsincreasedexponentiallyorevery9added,and99.999%availability

actuallyequatestolessthan5minutesdowntimeperyear.

91 92 93 94 95 96 97 98 99 00 01 02 03 04 05

12

10

8

6

4

2

0

Source Gartner Group

MIPS Shipped

Hardware Revenue

3000

2500

2000

1500

1000

500

0

year

$B


10/20

0

betweenFailures(MTBF)orthemainrameplatorm:

itisvariousdescribedasover20toover30,oreven

50years.

AnEagleRockAlliancesurveyrom2001identied

monetarydowntimecostsorarangeousers:iwas

greaterthan$50k/hourormorethanhalandover

$1m/houror8%.Systemshaveprobablybecomeeven

morecriticalsincethen,withcontinuingadoptiono

real-timeaccessandcommerceviatheInternet.That

surveyemphasiseswhyitmaybeworthpayingmoreor

ahighleveloavailability.

Themainrameplatormisalsoinherentlysecurebe-

causethereisarlessthreatovirusesorhacking.Not

onlywouldsuchathreatbehardertoproduce,butit

wouldhaveverylimitedimpactbecauseotheinter-

nally-securenatureotheplatorm.

Themainramecanalsodeliverhighlevelsoservice

duetoitsserverarchitecture,consistingoseparate

CentralProcessors(CPs)andInput/OutputProcessors

(IOPs),withsparesreadytotakeoverianyothemail.Thesearedeployedusingdispatchingalgorithmswhich

ensurethat,unlikesomeotherplatorms,processorsdo

nothavetowaitorI/Otocomplete.

Themainrameisalsoremarkableoritsscale,interms

othesheervolumesodataprocessed(processing

capacityoupto17,800MIPS),storedandtranserred

(upto170GBpersecond).

InTriggersorrereshingservers,June2005,Forrester

statethatthecurrentaveragecapacityutilisationor

Wintel-basedserverenvironmentsistypically8%to15%,and28%to45%orUnix/RISC-basedsystems

ormainrameslikeIBMzSeriesis65%to75%.

Mainramescan,anddo,happilyrunat100%utilisation

orlongperiods.

Soamainramecanbeullyloadedwithanenormous

volumeoworkwhichitwillcontinuetoprocessinde-

nitelyanduninterruptedly.

3.3SOFTWAREANDSTANDARDS

Inthersttwentyorsoyearsothemainrameslie,

IBMinventeditsowndeactostandards;indeed,itis

arguablethatithadtodoso.Butsincethen,withthe

adventodistributedcomputingandtheinternet,IBM

hasbeenbusysupportingindustryanddejurestan-

dards.

Inlinewithotheraspectsothemainrame,though,you

cancontinuetousetheoldstandardsalongsidethe

new:themainramesupportsTCP/IP(aswellasSNA

andVTAM),LDAPaccess(aswellasitsowndirectory

andsecuritycatalogues),OpenSource,DB2connec-

tion,lesharing,Tivoli,etc.

Amainrameenvironmentisinherentlyversatile:itcan

runarangeoITenvironments:

> Oldsotware:programswrittendecadesagoinCo-

bol,PL/1,FortranorevenAssemblerstillworkonthe

mostmodernsystem;

> Multipleapplicationenvironmentscanco-exist:

batch,online,interactiveandwebaccess;> Themostmodernplatormsarealsosupported:

Java,ServiceOrientedArchitecture(SOA,using

Websphere),C++,etc.

Amainramecanrun25-year-oldCobolandCICSap-

plicationsalongsidethosewhichhavebeenrecently

writtenusingSOAandWebsphere.This,althoughthe

hardware,operatingsystemandmiddlewarehaveall

undergonemajorchangesinthattime;backwards

compatibilityhasbeenensuredtoprotectinvestments

inhistoricsotware.

Thereareover1,300independentsotwarevendors

(ISVs)supportingthemainrameplatorm,anumber

whichisactuallyincreasingaccordingtoGartner.


11/20

3.4COSTOFOWNERSHIPORUSAGE

Inspiteotheirreputationorbeingexpensive,thereare

mainrameadvocates(e.g.theArcatiresearchgroup)

whoclaimthatmainramesareverycost-eective,when

comparedagainstUnixandWindowssystems,ona

per-userbasis.Theyclaimcostsasollows:

> Mainrame $4,500

> Unix $5,400

> Windows $8,000

Butitisdiculttomakeanapples-with-applescompar-

isoninthiscontext,anddieringanalysesdoproduce

dierentresults.Thisavourableanalysisisseenas

beingespeciallytruewheretherearealargenumbero

end-userswantingtousethesameunctionality,be-

causetheotherplatormsdonotscalesowell,andover

ave-yearperiod,becauseweareconsideringstable

workloads.

IBMthemselveshaveundertakenstudies,endorsed

byIlluminata,showingmainrameshaving5-60%cost

advantagesoverUnix,LinuxandWindowsalternatives.Thisispredicatednotonaone-or-onecomparison,but

onthecostorunning10-50applicationsononemain-

rameversus10-20bladesoragrido50systems.

Somespecicaspectsothisstudyareworthyourther

highlightingandconsideration:

> Themainramerequireslesselectricityandaircothan

many1U-rackedserversrunningthesameload.

Thisisverysignicantinamoderndatacentre

environment,wherethesecomponentsaremuch

moreoaconstraintthanspace.

> Thebalanceocostcomponentshavechangedradicallyinthelastdecade:

- peoplecostsrom14to43%;

- hardwarecostsrom65to20%.

ThereareclaimsobenchmarksshowingthatanSAP

environmentwithmorethan1,500-2,000usersisleast

expensivetorunonamainrame.Also,thatanymain-

rameenvironmentomorethan1,500MIPS(although

thegurevaries)istoodicultandcomplextomoveto

anotherplatorm.

Theoneweaknessinthecostanalysisormainrame

environmentsisthesotwarecomponent.Indeed,

accordingtoForresterthiscanamountto49%othe

costoownership.ThisispartlybecausesomeISVs

treattheplatormasacashcow.Developments

suchastheprovisionoaLinuxenvironmentmayhelp

toaddressthisaspect.Anotherpossibleremedyisthe

adventoorganisationswhichspecialiseinmigrating

environmentsromknowndicultISVspackagesto

lesstroublesomesotware.

Intermsopowerandcooling,mainrameswereprevi-

ouslyaconcernbecauseotheirneedorwater-cooling.

Butahighly-utilisedmainrameismuchmoreecient

thanaroomullounder-utilisedWindowsservers(as

perForrestersestimates).

Thecostoanyconversionalsoneedstobebrought

intothebalance:GartnerGrouphasstatedthat,While

theoverallnumberoIBMmainramecustomersis

declining(asthenumberosmallercustomersmigrat-

ingothemainrameeachyearexceedsthenumbero

rst-timecustomers),mostlargeenterpriseshaveac-

ceptedthattheirlegacyapplicationsuites(typicallywrit-

teninAssemblerorCOBOL)willneedtoremainonthe

mainrameenvironment.Evenithesameperormance

couldbeachievedondierentplatormsatalowercost,

theportingorrewritingneededtoachievethisisotenprohibitivelyexpensive.


12/20

3.5MAINFRAMESANDUTILITYCOMPUTING

UtilitycomputingisfavourothemomentinIT,butis

thisallquiteasnewasweareledtobelieve?Oristhe

mainrameaclassicimplementationoautilitycomput-

ingenvironment?25yearsago,manycompanieswere

doingutilityonmainrames:

> Theyranastandard(albeitproprietaryIBM)architec-

ture:S/370;

> Multiplebusinessunitswereprocessinginthesame

environment;

> Thesystemswereotenownedbysuppliers,whether

internalorexternal;

> Theyundertookcapacityplanning,perormanceand

availabilitymanagement;

> Theyusedsophisticatedtoolingtoautomate,charge,

secure,archive,

ThenalongcameDistributedComputing,consistingo:

> Dieringproprietaryinrastructurearchitectures,

> Dedicatedbox(es)perapplication,

> Dedicatedstorageperprocessorbox,etc.

Newtechnologiesnowprovidetheneededaspectsto

allowtheseotherenvironmentstodeliverusingsome

othesameservicecongurationsasthemainrame

alwayshasdone:e.g.SANsthatworkacrossmultiple

platorms,architecturalcompatibilitybetweensystems,

sophisticatedtoolingtomanagetheworkloadandpro-

visionsystemstorunit.

Theseacilitiesarenowbeingextendedbytheuseo

virtualisation:separatingthelogicalapplicationenviron-

mentromthephysicalsystem(s)onwhichitruns,and

allowingmultipleapplicationstorunonthesamebox.Virtualisationisnowwell-establishedintheUnixworld

andismakinggreatheadwayorWintelsystems.This

isanapproach,indeedatechnology,whichhasbeen

presentinthemainrameworldsincethe1970s.

So,inmanyways,currentmovestowardsutilitycom-

putingarereinventingthemainrame.


13/20

3

NEw dEvElOpmENTS wITHIN

THE maINframE wOrld

4.THEIBMMAINFRAMECHARTER

IBMdoesseemtorecognisethatthemainrameplat-

ormhasaperhaps-unairreputationasbeingabitoa

dinosaur.Thismaybeunairithetechnologyisjudged

dispassionately,butpartlyarisesbecauseosomegen-

uineconcerns,suchaswhethercustomerswillstillbe

abletoretaintheservicesosuitabletechniciansonce

therstgenerationosupportstahasallretired?

TherearegoodcommercialreasonswhyIBMshouldtry

tomaintainandenhancethisplatormaslongasitcan:it

isveryprotableandthereisverylittledirectcompetition.

IBMhasrespondedtothissituationwiththecreationo

theMainrameCharter:thisisasetoninestatements

(seebox)inwhichitpromisestocontinueinnovation,

oervalueandosterasupportcommunity.

Thisseemsaworthyintent,albeitonewhichisinits

owninterests.Mainramesdoseemtoengenderloyalty,

andtheregenuinelyisandhasoralongtimebeen

asenseocommunitywithinthemainrameworld,somewhatredolentothatwithintheOpenSource

community.Indeed,withtheuseozLinux,thosetwo

communitiesdoseemtotwelltogether.

4.SPECIALITYENGINES

Mostmulti-processingenvironmentsconsistoproces-

sorswhichallaccessthesameresourcesandperorm

equivalentunctions:SymmetricalMulti-Processingor

SMP.Sometimes,though,aprocessorcanbecong-

uredtotakeonparticulartasks,suchasthemathsorgraphicsprocessorsinaPC.

IBMhasannouncedanumberospecial-purpose

processingengineswhichcanbeinstalledintoamain-

rame.Thoseannouncedandshippedtodateare:

> IFL:IntegratedFacilityorLinux

> zIIP:theSystemz9IntegratedInormationProcessor,

orDB2

> zAAP:zSeriesApplicationAssistProcessor,orJava

Othersmaybeannouncedorofoadingotherunc-

tions,suchasWebServices,XMLparsing,TCP/IPandCICS.

TheIBMMainframeCharter

Itisourintentiontocontinueto:

ProvideInnovation:

>ProvideleadershipininnovationtoenhancetheuseoIBM

eServerTMzSeriestosupportincreasinglyintegratedandfexible

businessprocessesortheondemandbusiness.

>MaintainzSeriespositionasabenchmarkorfexible,ecient,and

responsiveplatormsorhighlycomplex,integratedenvironments

runningawiderangeomission-criticalworkloads.

>Improvetheautonomicandsel-managingcapabilitiesothe

zSerieswhileworkingtosimpliyuserprocessesandsystem

administrationtasks.

Offervalue:

>Enhancethevaluepropositionandlowerthecostocomputingo

zSeriessolutionsinawaythatiscompelling,clear,andconsistent.

>ExtendtheondemandcharacteristicsozSeriesservershighlighting

itsstrengthsasanenvironmentorusage-basedcomputing.

>IncreasetheabilitytoaccountorallocationanduseozSeries

resourcesinanondemandenvironment.

FosteraCommunity:

> SupportprogramsdesignedtoostervitalityinzSeriescommunity,

helpingtopromoteastrongapplicationportolioandworld-classsupportservices.

> Providetheskillsandexpertisetoassistcustomersindesigning,de-

veloping,anddeployingondemandsolutionsbuiltonaoundation

whosecornerstoneiszSeries.

> Leveragekeyopenstandardsandcommonstructurestoenchance

theuseozSeriesinlargeheterogeneousenvironments.


14/20

4

Theadvantagesothesespecialityenginescomepartly

romtheactthattheyofoadsomeotheprocessing

romthegeneral-purposeengineswithinthesystem.

Buttheyalsocomewithanincreasingpriceadvantage,

bothorthehardware(seegraph)andalsoasregards

chargingorthesotwarewhichrunswithinthesystem:

thisisnormallychargedonaper-processorbasis,but

ormostsotwaretheseenginesgetareeride.

4.3OPENSOURCE

Linuxseemstobeaveryattractiveoptionorthemain-

rameenvironment,bothorsystemstobeconverted

romapreviousMVSenvironmentandalsoasatarget

orconsolidation.ManyLinuxsystemswithvariable

loadcanbeconsolidatedintoonemainrameenviron-

ment,withtheaddedadvantageoin-machinetranser

speedsbetweenthem.

Linuxruns33%othenetnewMIPSbeingshipped,ac-

cordingtoGartnerGroup,and60%omainrameusers

areusingsomeLinuxontheplatorm.Almost225ISVscurrentlydeliverover600applicationsrunningonLinux

ontheIBMmainrame,accordingtoBloorResearch.

Linuxskillsarereadilyavailableandcaneasilybeported

tothisplatorm.

4.4SERVICEORIENTEDARCHITECTURE(SOA)

Manybusinessescontinuetorelyupontheirmainrame-

basedapplicationssystemstoprovidecriticaltransac-

tionalbusinesssupport.Buttheyneedtondawayto

openupthatplatorm,stopitbeingsuchanisland

andallowittotakeitspartinthewidersetupapplica-

tionsandITsystemswithintheenterprise.

ServiceOrientedArchitecture(SOA)isanapplication

developmentandprocessingmodelwhichisverymod-

ular,andallowsapplicationunctionalitytobebroken

intocomponentsandexposedtootherapplications.

CharacteristicsoSOA:

> Standards-basedcomponentsreusedandcombined

asrequired;

> Sel-describing:standardormatorequestand

response;

> Sel-contained:nottightlycoupled;

> Locationindependent:intermsonetworkor

geography.

WebServicesreerstothewayinwhichtheseSOA

servicecomponentscanbemadeaccessibleviaaweb

(intranetorinternet)interace,makingthemacces-

sibleromotherpartsotheorganisationorevenother

organisations.

SOAdependsuponhavingbuildingblocksounctional-

ity:asystemorsystemswhichhostparticularinormation

orperormparticulartaskswheninvokedinaspecifc

2001 2002 2003 2004 2005

120%

100%

80%

60%

40%

20%

0%

IBMCostperMIPS Source Gartner Group

General Purpose

Special Purpose


15/20

5

way.Thissuccinctlydescribesmanylegacymainrame

environments,whichiswhytheyareparticularlyame-

nabletobeingwrappedinanSOAenvironment.

TechnologiestoSOA-enablelegacy(e.g.CICS)applica-

tionsuseWebsphereasaront-end.Websphereisthe

predominantJava-basedplatormorthesedevelop-

mentsinanIBMenvironment.

Ilegacysystemsneededtoprovidebusinessprocess

supportcanberont-endedbyanSOAenvironment,

theycanthenbeknittedtogetherwithothersystems,

makingupacompleteenvironmentromthesemodular

components.

4.5GREYINGOFTHEWORkFORCE

Fromacompletelydierentperspective,thereareears

oashortageoavailablemainrameskillsastheIT

supportpopulationages,butmanyotheseandother

developmentsmayalsohelpaddressthatconcern:

> Mainramesaremucheasiertosupportthesedays:previouslyanarmyohighly-trainedspecialistswas

required,butthetoolstomanageamainrameplat-

ormhaveimprovedenormously,soroutineunctions

canbedonebylesser-skilledresourceswithmuch

lessriskandexposure:

Apulsecheckacilitycanbeusedtotakea

snapshotoanenvironmentandproducethe

commands(usingtoolssuchasSMP/E)to

congurethesystemsasrequired;

Systemdumpsnolongerneedtobeanalysed

in-house:ratherthesystemwillindicatetowhich

oyoursotwaresuppliersitshouldbesentorresolution;

> ThedevelopmentoaMainrameCommunityaspart

otheMainrameCharterincludesmakingmain-

ramesavailabletocollegesacrosstheworld,sothat

studentscangainhands-onexperienceasparto

theirlearningoITskills.IBMnowhasmorethan

150universitiesaroundtheworld(50%inthe

Americas,30%inEuropeand20%inAsia)enrolled

initsAcademicInitiativeprogram;

> Linuxalreadyhasanenormousamountoadherents,

isverywelladoptedwithinacademiccirclesandhas

itsowncommunitysupport.CombiningthisOpen

Sourceapproachontothemainrameplatormcould

alsoyieldenormousbenetsandmakeskillsmuch

moreavailable;

> TheadventoarchitecturessuchasSOAmeansthat

thoseusingtheplatormasacomponentotheir

applicationsenvironmentneedmuchlessknowledge

otheunderlyingplatorm.Indeed,theymaynoteven

knowonwhatplatormaspecicunctionispro-

vided;

> ITservicesupplymodelssuchasoutsourcingand

o-shoringmeanthatuserscancontractanyremain-

ingproblemtosomeoneelse,whocanbenetbothrommuch-greatereconomiesoscaleandromthe

useoawell-trainedand-disciplinedworkorcein

othergeographies.


16/20

6

Ratherthanbeingtreatedasbeinglegacy,themain-

rameplatormcanjustbeseenasanotherplatorm

withinarangeocurrentoptions,withitsownperor-

manceandcostcharacteristics.Andasonewhichulls

thatrolewhileitisstillrunningthevastnumberobusi-

ness-criticalapplicationsitbringsasitsheritage.

Themainramehasuniquecharacteristics.Inmost

cases,iteectivelydelivers100%availability:thereisno

lowQualityoServiceoptionormainrameservices,

whichhaveaMTBFoover20years.

THE maINframE

buSINESS CaSE

Torunmainrameseciently,however,youdoneeda

certaincriticalmass.Itisdebatablewhatthatlevelis,

butthebreakpointseemstobeinthescaleo7,000

MIPS.Atthatpointyoucanmakeecientuseothe

ParallelSysplexenvironmentandthescalinglicence

ees.So,manyusersarenowoptingtohavetheirmain-

ramesrunbyaserviceprovider,whohasthecritical

massobothsystemsandskillsinordertomaintainand

developtheenvironment.

Perorm a ull assessment o currentmainrame applications and inrastructure,

including criticality and prognosis

Canapplications be

replaced by standard applicationsor moved to another

platorm?

Compare TCO with projectedTCO or alternative platorm

Seek a reliable andpredictable migrationprocess or oering

Are thererealistic levels o savings

to be made?

Seek to optimise and consolidate

the mainrame environment

Use mainrame asconsolidation target or

other systems?

Add other appropriate systems

to the mix under consideration

Do it yoursel

(Out-)sourcing policy?

Move onto less expensiveh/w + s/w combination

Aresystems modern and

up-to-date?

Solve it yoursel?

Determine strategy or urther lie-cycle maintenanceo both the application and the platorm

Outsource


17/20

Conclusions:

> Iyoualreadyhaveamainrameenvironment,you

mayverywellndthatthebestapproachistokeep

it,andevenconsolidateothersystemsontoit,

> Possiblyyoucouldlooktogetitmanagedoryou,

eveniyouretainotherplatormsyoursel:youdont

havetoownamainrametobeabletouseone;

> Simplicationiskeytothemanagementothese

environments:createasingle,coherentenvironment;

> Thesesystemscouldbethetargetorlarge-scale

consolidation:youcanrunhundredsoUnixorLinux

imagesononemainrame.

Usersomainrameenvironmentcanalsobestposition

ortheuturebyreducingthebarriersbetweenmain-

rameandnon-mainrameplatorms.Thisincludesusing

technologiessuchasLinuxandSOA,describedelse-

where,andstandardoperatingprocesses,suchasITIL.

Thelessthatamainramesitsinastand-alonesilo,

themoreitcanbeintegratedtotakeitspartinuture

ITservices,andthelessriskthereisohavingdiculties

supportingitintheuture.

So,theslumberingdinosaurisawake,andisready

andabletomaintainitsrightulplaceintheportolioo

modernITsolutions.


18/20

7 April IBM announces the System/360: a amily o ve increasingly powerul computers that run the same operating

1964 system and can use the same 44 peripheral devices.

1968 CICS (Customer Inormation Control System) is introduced. It allows workplace personnel to enter, update and

retrieve data online.

1968 S/360 model 85 introduces high speed cache memory, making high-priority data available 12 times aster than ever beore

and laying the oundation or the same cache memory ound across much o todays computing technology.

1970 The Plug Compatible Manuacturer (PCM) market arises: by 1970, over 80 companies have over 200 products compatible

with the S/360 architecture and its peripheral devices.

1970 The S/370 as successor o the S/360 is introduced. The S/370 Model 145 is the rst computer with a ully integrated

monolithic memory (all resistors, capacitors and diodes on a single slice o silicon). Beore this semiconductor technology,

magnetic core technology was used.

1971 Amdahl comes with a clone o the S/370. Gene Amdahl was chie engineer or the IBM S/360 program,

he starts the Amdahl cooperation. The Amdahl machines are air-cooled whereas the IBM machines are water-cooled.

1972 IBM announces VM virtualization, with the VM/370 operating system.

1972 SAP develops a revolutionary ERP-system or S/370. For the rst time, companies can place orders and track inventory

in real time.

1976 SAS sotware creates a new competitive edge: business intelligence. With SAS you can get intelligence out o raw data.

1981 The successor o the S/370 is the 3081, which uses less energy and space than its predecessors. With it comes eXtended

Architecture (XA), providing dynamic channels and 31-bit (2 GB) addressing.

1983 MVS/XA shipped: an operating system to exploit the new architecture.1985 Amdahl introduces MDF (Multiple Domain Feature) the rst hardware partitioning tool on the Amdahl 470 mainrames.

1988 IBM introduces PR/SM , the answer rom IBM to Amdahls MDF. Now hardware partitioning with Logical Partitions (LPARs)

are possible on IBM mainrames.

1988 DB2, IBMs relational database management system is introduced.

1988 MVS/ESA and VM/XA operating systems were introduced, relieving the memory constraints which limited the size

o applications by using new architectural constructs.

1994 The Parallel Sysplex is announced, which makes it possible to share 32 mainrames in a single cluster.

1994 UNIX on the mainrame was announced. OpenEdition, later renamed to Unix System Services is an integral part o the

operating system OS/390 (In 2006 the OS is z/OS)

1995 CMOS based processors are introduced into the mainrame environment, setting the new roadmap or modern mainrame

technology. CMOS machines required 1/20th o the energy and 1/10th o the foorspace compared to the older machines.

1999 Capacity Upgrade on Demand (a utility-like commercial construct) provides extra capacity which can be turned on as

dictated by business needs.

1999 Linux appears on the S/390, combining the fexibility o open source computing with the legendary scalability and

reliability o the mainrame.

2000 IBM introduces the zSeries mainrame and the 64-bit operating system z/OS.

2003 The Mainrame Charter is introduced by IBM. It articulates IBMs commitment to deliver innovative solutions,

expand zSeries value and oster a zSeries community in order to meet customers on demand business requirements.

2003 The zIFL (specialized Linux processor) is introduced on the zSeries.

2004 The zAAP (specialized JAVA processor) is introduced on the zSeries

2005 The z9 amily o servers is introduced delivering granularity in the size o servers rom small to very large:rom 26 to 18,000 MIPS on one machine.

2005 The zIIP( specialized DB2 processor) is announced or the z9 servers.

appENdIx a: a SHOrT HISTOry

Of THE maINframE


19/20

6.REFERENCES

ArchitectureotheIBMSystem/360,Amdahletal,IBMJournaloR&D,19642005mainramemarketoutlook,ForresterResearch,February2005

Triggersorrereshingservers,ForresterResearch,June2005

IBMmainramesendurancewillposenewchallengesorusers,GartnerGroupG00138934,May2006

Areshlookatthemainrame,PMPResearch,2005

Thedinosaurmythanupdate,ArcatiResearch,2005

IBMSystemzTCO:manbitesdog,Illuminata,November2006

IntroducingUtilityComputing,AtosOrigin,October2006

6.ACkNOWLEDGEMENTS

TheeditorialteamorthiswhitepaperwasledbyMickSymonds,withcontributionsromHerbertVoskuil,PaulBlesandotherAtosOriginsta.

Formoreinormation,pleasecontactyourlocalAtosOriginrepresentative,

orvisithttp://www.atosorigin.comore-mail:[email protected]

COlOpHON

Mainramesperormancehastraditionallybeendescribedintermsomillionsoinstructionspersecond(MIPS),asa

simpleindicationospeed.Thisisnotassimpleasitsounds,becausethemainrameusesacomplexinstructionset

sothatthecontentsandeectooneinstructioncanvaryenormously.

Thedicultyiscompoundedbyactorssuchasvirtualisationandmulti-processing,andtheneedtobalanceI/O

processingwithexecutionoinstructions.

ThetermMIPShasotenbeenparodiedasMeaninglessIndicatoroProcessingSpeed,butnosimplealternativehas

emerged.Indeed,theemergingmarketorgeneral-purposeutilitycomputingsuersromthelackoasimpleunito

measureequivalenttotheMIPS.

Withinthesystem,ServiceUnitsareusedorworkloaddespatchandbalancing.Thereareapproximately50SUs

perMIPS.

Separately,theconceptoMillionsoServiceUnits(MSUs)aroseoraspectssuchassotwarelicensing.Conusingly,

thesearenotmillionsotheServiceUnitsmeasuredabove:therearebetween5and8.5MIPSperMSU.Thegure

variesbecauseIBMusesthemtoencouragemigrationtonewplatorms.

IBMhavetriedtoacilitateworkloadestimateandcapacityplanningbypublishingLargeSystemPerormance

Reerence(LSPR)tables,buttheseareartoocomplextoallowsimplecomparisons.

Thereisanindependentanalyst,CherylWatson,whohasmadeanichebusinessoutopublishingchartsothevari-

oussystemsperormanceordierentworkloadsandoperatingsystemslevels,alongwithRulesoThumbastohowtheyshouldbedeployed.

appENdIx b: wHaT arE mIpS,

mSuS aNd SErvICE uNITS?


20/20

Atos Origin

Papendorpseweg 93

3528 BJ UTRECHT

Tel: (088) 265 55 55e-mail: [email protected]

www.atosorigin.nl

n.

A to So Rig in Mainframes in Perspective Whitepaper 2

Documents