VSAM Performance Tuning

8/9/2019 VSAM Performance Tuning

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WAVV 2007, Green Bay, WI

AcknowledgementAcknowledgement

With grateful thanks to DanWith grateful thanks to Dan

JandaJanda, The Swami of VSAM,, The Swami of VSAM,from whom most of thisfrom whom most of this

presentation was stolenpresentation was stolen


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AbstractAbstract

This presentation gives an overview of VSAM & its components.This presentation gives an overview of VSAM & its components.

We take a look at what a VSAM file really looks like and how toWe take a look at what a VSAM file really looks like and how to

soup up its performance.soup up its performance.

We also look at some common mistakes and how to avoid them.We also look at some common mistakes and how to avoid them. This presentation and its materials are copyrighted andThis presentation and its materials are copyrighted and

developed by John Mycroft from a presentation originallydeveloped by John Mycroft from a presentation originally

copyrighted by Dancopyrighted by Dan JandaJanda. Permission is granted for WAVV to. Permission is granted for WAVV to

reproduce this presentation for distribution to its members at nreproduce this presentation for distribution to its members at noo

charge.charge.

Trademarks:Trademarks:

IBM, VSE, VSE/ESA,IBM, VSE, VSE/ESA, zVSEzVSE, CICS & DL/I are trademarks or registered, CICS & DL/I are trademarks or registered

trademarks of the IBM Corporationtrademarks of the IBM Corporation The Swami of VSAM is a trademark of DanThe Swami of VSAM is a trademark of Dan JandaJanda..


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VSE/VSAM OverviewVSE/VSAM Overview

Virtual Storage Access MethodVirtual Storage Access Method For disk filesFor disk files

SequentialSequential Entry Sequence Dataset or ESDSEntry Sequence Dataset or ESDS

Begin at the beginning, go onBegin at the beginning, go on tiltil you get to the end andyou get to the end and

then stopthen stop IndexedIndexed Keyed Sequence Dataset or KSDSKeyed Sequence Dataset or KSDS

Process by key or sequentially or a mixtureProcess by key or sequentially or a mixture

DirectDirect Relative Record Dataset or RRDS (fixed) orRelative Record Dataset or RRDS (fixed) or

VRDS (variable)VRDS (variable) Calculate a records location in the file to access itCalculate a records location in the file to access it

Alternate index (AIX)Alternate index (AIX) gives an alternative route to agives an alternative route to aKSDSKSDS

Allows unique & nonAllows unique & non--unique keysunique keys


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unc onaunc onaareasareas

CatalogCatalog Volume & file informationVolume & file information

Usage statisticsUsage statistics Disk space managementDisk space management

Space allocation including secondarySpace allocation including secondaryallocationsallocations

VSAM and VSAM/SAM filesVSAM and VSAM/SAM files

System filesSystem files

LibrariesLibraries


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VSE/VSAM Functional areasVSE/VSAM Functional areas

IntegrityIntegrity

PerformancePerformance Data transfer sizeData transfer size

BufferingBuffering

Backup / restoreBackup / restore File sharing between jobs andFile sharing between jobs and

systemssystems


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Processing a VSAM fileProcessing a VSAM file Sequentially (ESDS)Sequentially (ESDS)

Forward or backwardForward or backward

Keyed access (KSDS)Keyed access (KSDS) Direct by full or partial (generic) keyDirect by full or partial (generic) key

Sequentially, forward or backwardSequentially, forward or backward

Skip sequential, forward or backwardSkip sequential, forward or backward

Addressed access (RRDS, VRDS)Addressed access (RRDS, VRDS)

Direct, by record addressDirect, by record address Sequential & skip sequentialSequential & skip sequential

Alternate Index AccessAlternate Index Access Same as keyed accessSame as keyed access

--


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How VSAM stores dataHow VSAM stores data

Were going to look atWere going to look at How VSAM stores records logically on diskHow VSAM stores records logically on disk

Performance considerationsPerformance considerations How VSAM physically stores data on diskHow VSAM physically stores data on disk

Disk space usage calculationsDisk space usage calculations

Optimizing disk capacityOptimizing disk capacity

Performance considerationsPerformance considerations VSAM jargonVSAM jargon

Control IntervalControl Interval

Control AreaControl Area

CI & CA splitsCI & CA splits FreespaceFreespace

RDF, CIDFRDF, CIDF


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VSAM JargonVSAM Jargon

Control Interval (CI)Control Interval (CI)Smallest unit of data transfer between main &Smallest unit of data transfer between main &

disk storagedisk storage In other words, when you read a record, VSAM readsIn other words, when you read a record, VSAM reads

the whole CI that contains that recordthe whole CI that contains that record

Think of it as the same as a block of records in aThink of it as the same as a block of records in asequential file if you like (though its laid outsequential file if you like (though its laid out

differently)differently) A CI can initially contain 1 or more recordsA CI can initially contain 1 or more records

More can be insertedMore can be inserted

Some or all can be deletedSome or all can be deleted

When you try to add a new record to a CI with noWhen you try to add a new record to a CI with noroom, a CI split takes placeroom, a CI split takes place more about that latermore about that later


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Layout of a control intervalLayout of a control interval

ALL VSAM FILES ARE VARIABLE LENGTHALL VSAM FILES ARE VARIABLE LENGTH Even if all the records are the same sizeEven if all the records are the same size

RecRec 11 RecRec nn 1 to n logical records of any length1 to n logical records of any length FreespaceFreespace Unused space in CI for insertingUnused space in CI for inserting

recordsrecords or making existing records longeror making existing records longer

RDFsRDFs 3 byte record descriptor field3 byte record descriptor field

ESDS/KSDSESDS/KSDS one per record length, one for allone per record length, one for allconsecutive records of same lengthconsecutive records of same length

RRDSRRDS one per numbered record slotone per numbered record slot

CIDFCIDF 4 byte Control Interval Descriptor Field4 byte Control Interval Descriptor Field

RecRec 11 RecRec 22 RecRec 33 RecRec FreespaceFreespace RDFsRDFs CIDFCIDF


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Control Area (CA)Control Area (CA)

A CA is a group of CIs. In a KSDS, all the data CIsin a CA are indexed by one index CI

CI 0CI 0 CI 1CI 1 CI 2CI 2 CI 3CI 3 CI 4CI 4 CI 5CI 5 CI 6CI 6 CI 7CI 7 CI 8CI 8 CI 9CI 9

CI10CI10 CI11CI11 CI12CI12 CI13CI13 CI14CI14 CI15CI15 CI16CI16 CI17CI17 CI18CI18 CI19CI19


CA size is the smallest of :CA size is the smallest of :One cylinder orOne cylinder or

The size of the primary allocationThe size of the primary allocation

The size of the secondary allocationThe size of the secondary allocationThe number ofThe number ofCIsCIs per CA depends on the device and the CIper CA depends on the device and the CIand CA sizesand CA sizes

It is generally a good idea to go for the biggest CA possibleIt is generally a good idea to go for the biggest CA possible


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Index Control Interval (Index CI)Index Control Interval (Index CI)

A CI in an index containing pointers toThe next level in the index or

The Data CI in the CA this is referredto as a Sequence Set CI

CI 0CI 0 CI 1CI 1 CI 2CI 2 CI 3CI 3 CI 4CI 4 CI 5CI 5 CI 6CI 6 CI 7CI 7 CI 8CI 8 CI 9CI 9



Index CIIndex CI


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Index and data structureIndex and data structure

Balanced treeBalanced tree

Sparse indexSparse index Always just 1 highAlways just 1 high--level index CIlevel index CI

There can be 0 to many intermediateThere can be 0 to many intermediate

level indexlevel index CIsCIs

There can be one or more lowThere can be one or more low--levellevel

(sequence set) index(sequence set) index CIsCIs.. If there is only 1 sequence set CI, itIf there is only 1 sequence set CI, it

is also the highis also the high--level index CIlevel index CI


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And now the bit youve allAnd now the bit youve all

been waiting forbeen waiting for


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Performance rules of thumbPerformance rules of thumb

Use largest data CI possible,Use largest data CI possible,

especially for sequential workespecially for sequential work Use as small an index CI as youUse as small an index CI as you

can (but not too small!)can (but not too small!)

Use large data CAUse large data CA allocateallocate

primary and secondary as atprimary and secondary as at

least 1 cylinderleast 1 cylinder Avoid too many extents /Avoid too many extents /

allocationsallocations


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Allocation calculationsAllocation calculations

CICI freespacefreespace ==

CI Size *CI Size * FreespaceFreespace %% Number of records per CINumber of records per CI

Fixed length:Fixed length:

(CI Size(CI Size --1010 FreespaceFreespace) / LRECL) / LRECL

Variable length:Variable length:

(CI Size(CI Size --77 FreespaceFreespace) / (Average) / (AverageLRECL +3)LRECL +3)


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Allocation calculationsAllocation calculations

CalculateCalculate FreespaceFreespace in each CAin each CA

Get number ofGet number ofCIsCIs per CA fromper CA fromLISTCAT or device characteristicsLISTCAT or device characteristics

(3390, 12 x 4K(3390, 12 x 4K CIsCIs/track, 180/cyl)/track, 180/cyl)

CACA freespacefreespace = No of= No ofCIsCIs per CA *per CA *CACA FreespaceFreespace %, rounded up%, rounded up

Number ofNumber ofCIsCIs loaded per CA =loaded per CA =

CIsCIs per CAper CA CACA freespacefreespace

Number of records loaded per CA =Number of records loaded per CA =

LoadedLoaded CIsCIs in CA * No ofin CA * No ofrecsrecs in CIin CI


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VSAM CatalogsVSAM Catalogs

Exactly one master catalogExactly one master catalog

Assigned at IPL with DEF CAT orAssigned at IPL with DEF CAT or DEFINE MCAT IDCAMS commandDEFINE MCAT IDCAMS command

User catalogsUser catalogs 0 to many0 to many

No more than 1 per volumeNo more than 1 per volume

Catalog can own multiple spacesCatalog can own multiple spaces

on a volumeon a volume Many catalogs can own space on aMany catalogs can own space on a

volumevolume


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VSAM CatalogsVSAM Catalogs

Catalog contains :Catalog contains :--

SelfSelf--describing recordsdescribing records User catalog pointersUser catalog pointers

Volume definitionsVolume definitions

Space definitionsSpace definitions

Cluster (file) definitionsCluster (file) definitions

Component (data, index) definitionsComponent (data, index) definitions AIX & Path definitionsAIX & Path definitions


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Catalog recommendationsCatalog recommendations

Use naming conventionsUse naming conventions Name Cluster, Data and Index componentsName Cluster, Data and Index components

explicitlyexplicitly Use partition / system independent namesUse partition / system independent names

where applicablewhere applicable

SeparateSeparate Files seldom defined or deletedFiles seldom defined or deleted

Files often defined or deletedFiles often defined or deleted

Online critical filesOnline critical files Batch filesBatch files

Multiple basketsMultiple baskets all the eggs wontall the eggs wont

get brokenget broken


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More recommendationsMore recommendations

Dont use recoverable catalogsDont use recoverable catalogs

Hangover from 2314 / 3330Hangover from 2314 / 3330 Backup is vastly betterBackup is vastly better

IDCAMS,IDCAMS, FaverFaver,, MaxbackMaxback, Dr D,, Dr D,

useruser--written written


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CI & CA splits andCI & CA splits and freespacefreespace

You try to insert a record in a CIYou try to insert a record in a CI

or extend a record already thereor extend a record already there

If there is enough free space inIf there is enough free space in

the CI, everyone moves up,the CI, everyone moves up,

record is inserted and CIrecord is inserted and CIrewrittenrewritten

BUT what if there isnt enoughBUT what if there isnt enoughfree space????free space????


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CI & CA splitsCI & CA splits

CI splitCI split 4 physical4 physical IOsIOs

Set Split in progress, write CISet Split in progress, write CI Move half of records to new CI &Move half of records to new CI &

write itwrite it

Update sequence set, write indexUpdate sequence set, write indexCICI

Erase moved records from old CI,Erase moved records from old CI,turn off Split in progress,turn off Split in progress, witewite

old CIold CI

BUT..BUT..


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Failure in CI splitFailure in CI split

System failureSystem failure

Corrected next time CI is updatedCorrected next time CI is updated No free CI in the CANo free CI in the CA

CA split is neededCA split is needed

RememberRemember 1 physical IO =1 physical IO =

30,00030,000 40,000 CPU40,000 CPUinstructionsinstructions


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CA SplitCA Split

MANY physical reads and writesMANY physical reads and writes Set Split in progress, write sequenceSet Split in progress, write sequence

set CIset CI Maybe get new extentMaybe get new extent

Format new CA at HURBA positionFormat new CA at HURBA position

Read / write half ofRead / write half ofCIsCIs to new CAto new CA

Write new sequence set CI for new CAWrite new sequence set CI for new CA

Update higher level indexUpdate higher level index CIsCIs Erase movedErase moved CIsCIs from old CA, writefrom old CA, write

emptyempty CIsCIs

Write updated original sequence set CIWrite updated original sequence set CI


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RecommendationsRecommendations

Dont worry about CI splitsDont worry about CI splits

Avoid excessive CA splits byAvoid excessive CA splits bydefining CAdefining CA freespacefreespace

Dont do aDont do a reorgreorgjust becausejust because

you have done n CI / CA splitsyou have done n CI / CA splits


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ToTo reorgreorg or not toor not to reorgreorg??

Weve done 1000 CA splitsWeve done 1000 CA splits

betterbetter reorgreorg!!

Inserts tend to be clusteredInserts tend to be clustered

CI / CA split createsCI / CA split creates freespacefreespace

where it is needed, allows fasterwhere it is needed, allows faster

insertsinserts

ReorgReorg gets rid ofgets rid offreespacefreespace,,causing more CI / CA splitscausing more CI / CA splits


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RecommendationsRecommendations

Avoid frequentAvoid frequent reorgsreorgs

Once a split has occurred, theOnce a split has occurred, theprocessing cost has been paidprocessing cost has been paid

Understand your applicationUnderstand your application

1 hot spot1 hot spot

Little distributedLittle distributed freespacefreespace let it splitlet it split

Many hot spotsMany hot spots Little distributedLittle distributed freespacefreespace let it splitlet it split

Even distributionEven distribution no hot spotsno hot spots

Use distributedUse distributed freespacefreespace


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FreespaceFreespace

3% of each CI is empty

5% of CIs in each CA are empty

3% of 2048 = 61 bytes = 0records (or, at most, 1)

5% of 315 CIs per CA = 16 CIs


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FreespaceFreespace

3% CI freespace where CISZ=2048

and average LRECL=120No room in this CI for an averagelength record

lAlt i ff


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AlteringAltering freespacefreespace

InitialInitial freespacefreespace set via DEFINEset via DEFINE

egeg 10% of CI and 5% of CA10% of CI and 5% of CA

If inserts are clustered, considerIf inserts are clustered, consider

DEFINE with 0%DEFINE with 0% freespacefreespace, then, then

Load the file thenLoad the file then

ALTERALTER freespacefreespace to nonto non--zerozero

S iSt i


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StringsStrings

VSAM allows multiple concurrentVSAM allows multiple concurrent

processing e.g.processing e.g.

CICS transactionsCICS transactions

BrowsingBrowsing

UpdatingUpdating

Placeholders (strings) hold filePlaceholders (strings) hold file

location infolocation info

Sh d / h d


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Shared / nonShared / non--shared resourcesshared resources

NonNon--shared resources (NSR)shared resources (NSR)

Each string has its own buffersEach string has its own buffers

Multiple copies of a CI may be inMultiple copies of a CI may be in

memorymemory

Works well for batchWorks well for batch

Local Shared Resources (LSR)Local Shared Resources (LSR)

Many strings share a pool of buffersMany strings share a pool of buffers Only 1 copy of a CI in the poolOnly 1 copy of a CI in the pool

Ideal for onlineIdeal for online

R d tiR d ti NSRNSR


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RecommendationsRecommendations -- NSRNSR

NonNon--shared resourcesshared resources

Each string must have enough indexEach string must have enough index

buffersbuffers

BadBad 1 buffer (old default)1 buffer (old default)

OKOK 1 buffer per index level (new default)1 buffer per index level (new default)GoodGood enough buffers for all high levelenough buffers for all high level

indexes + 1 moreindexes + 1 more

BestBest enough buffers to hold entire indexenough buffers to hold entire index

R d tiR d ti LSRLSR


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RecommendationsRecommendations -- LSRLSR

Local Shared Resource buffersLocal Shared Resource buffers

Same index buffer needs as NSRSame index buffer needs as NSR

(buffers are per pool, not per(buffers are per pool, not per

string)string)

Monitor VSAM LSR stats to makeMonitor VSAM LSR stats to makesure BUFNI keeps up with indexsure BUFNI keeps up with index

growthgrowth

Monitor data buffers for high hitMonitor data buffers for high hitratesrates

IO ith NSRIO with NSR


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IO with NSRIO with NSR

VSAM uses chained IO to readVSAM uses chained IO to read

ahead and write behindahead and write behind

Better to read manyBetter to read many CIsCIs in one IOin one IO

Block bigBlock big

Large CI sizesLarge CI sizes Be aware that VSAM will splitBe aware that VSAM will split CIsCIs intointo

smaller blocks to save spacesmaller blocks to save space

EgEg 3390 with 32K CI gets written as 2 x3390 with 32K CI gets written as 2 x16K blocks giving 1.516K blocks giving 1.5 CIsCIs = 48K/track= 48K/track

Buffer bigBuffer big

to 1 to 1 cylcyl of BUFND to minimize IOof BUFND to minimize IO

IO ith LSRIO with LSR


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IO with LSRIO with LSR

VSAM reads 1 CI at a time, evenVSAM reads 1 CI at a time, even

for sequential processingfor sequential processing

Monitor your statsMonitor your stats


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Monitor your statsMonitor your stats

LISTCAT before and after critical jobLISTCAT before and after critical job

Data & IndexData & Index EXCPsEXCPs the fewer the better.the fewer the better.

IndexIndex EXCPsEXCPs should be close to number ofshould be close to number ofindexindex CIsCIs..

Job Accounting dataJob Accounting data

IO count by deviceIO count by device OveralOveral CPU & IO activityCPU & IO activity

CICS statsCICS stats

Shows logical / physical IO counts by fileShows logical / physical IO counts by file LSR pool hits and missesLSR pool hits and misses

VSAM buffer statsVSAM buffer stats in VSE/ESA examples docin VSE/ESA examples doc

LSR is in 31 bitLSR is in 31 bit use LOTS but dont pageuse LOTS but dont page

Sharing VSAM datasetsSharing VSAM datasets


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VSAM can share files among partitionsVSAM can share files among partitions

And among VSE systemsAnd among VSE systemsBUTBUT

TANSTAAFL (Robert Heinlein)TANSTAAFL (Robert Heinlein)Sharing is not a performanceSharing is not a performance

option (Danoption (Dan JandaJanda))Its your gun and your footIts your gun and your foot

(Steve Huggins)(Steve Huggins)



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Sharing is based onSharing is based on

The type of sharing you ask forThe type of sharing you ask for

(SHAREOPTIONS)(SHAREOPTIONS)

VSE Lock Table within a single VSEVSE Lock Table within a single VSE

systemsystem VSE Lock File when sharing across VSEVSE Lock File when sharing across VSE

systemssystems

VSE sharing mechanism is notVSE sharing mechanism is not

compatible withcompatible with zOSzOS oror zVMzVM



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Sharing at OPEN / CLOSE timeSharing at OPEN / CLOSE time

Entries checked and placed in / removedEntries checked and placed in / removed

from lock tablefrom lock table

If DASD volume is added as shared (ADDIf DASD volume is added as shared (ADD

cuu,SHRcuu,SHR), it is added to lock file), it is added to lock file VSE & VSAM allow concurrentVSE & VSAM allow concurrent

processing to protect againstprocessing to protect againstconcurrent updates messing up the fileconcurrent updates messing up the file



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Integrity classesIntegrity classes your choiceyour choice NO INTEGRITYNO INTEGRITY VSE & VSAM provide no dataVSE & VSAM provide no data

protection: its all up to you. Your data can beprotection: its all up to you. Your data can bemessed up.messed up.

WRITE INTEGRITYWRITE INTEGRITY VSE & VSAM protect againstVSE & VSAM protect againstconcurrent updatesconcurrent updates

READ INTEGRITYREAD INTEGRITY VSE & VSAM make sure yourVSE & VSAM make sure yourprograms always see the latest version of aprograms always see the latest version of arecordrecord

The priceThe price Higher levels & broader scopes of integrity leadHigher levels & broader scopes of integrity lead

to more CPU and IO activityto more CPU and IO activity

SHAREOPTIONSSHAREOPTIONS


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SHAREOPTIONSSHAREOPTIONS

ReadyReady FireFire AimAim

Set in DEFINE CLUSTERSet in DEFINE CLUSTER Get it wrong & be prepared to sufferGet it wrong & be prepared to suffer

If a disk drive isnt shared betweenIf a disk drive isnt shared between

VSEsVSEs, dont ADD it with SHR as this, dont ADD it with SHR as this

causes lock file IOcauses lock file IO

SHAREOPTIONS & LockingSHAREOPTIONS & Locking


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SHAREOPTIONS & LockingSHAREOPTIONS & Locking

SHR(1) 1 output OR many inputSHR(1) 1 output OR many input External lock at OPEN, unlock at CLOSEExternal lock at OPEN, unlock at CLOSE

SHR(2) 1 output AND many inputSHR(2) 1 output AND many input External lock at OPEN, unlock at CLOSEExternal lock at OPEN, unlock at CLOSE

SHR(3) No checking or lockingSHR(3) No checking or locking

Prepare for garbage dataPrepare for garbage data SHR(4) Many output in one VSE & manySHR(4) Many output in one VSE & many

inputinput OPENsOPENs across allacross all VSEsVSEs

External lock at OPEN, unlock at CLOSEExternal lock at OPEN, unlock at CLOSE

External lock at access, unlock at releaseExternal lock at access, unlock at release

SHR(4 4) Many outputSHR(4 4) Many output OPENsOPENs across allacross allVSEsVSEs + many input+ many input OPENsOPENs Locks same as SHR(4)Locks same as SHR(4)

Alternate indexes (AIX)Alternate indexes (AIX)


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Alternate indexes (AIX)Alternate indexes (AIX)

An AIX is a VSAM KSDS, acting asAn AIX is a VSAM KSDS, acting as

a pointer file for another filea pointer file for another file

Target file (Base Cluster) can beTarget file (Base Cluster) can be

KSDSKSDS pointers are KSDS key valuespointers are KSDS key values

ESDSESDS pointers are Relative Bytepointers are Relative Byte AddrsAddrs Great for multiple or nonGreat for multiple or non--unique keysunique keys

BUTBUT

Processing via an AIX needs IO to bothProcessing via an AIX needs IO to both

the AIX and to the base clusterthe AIX and to the base cluster

Setting up an AIXSetting up an AIX


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Setting up an AIXSetting up an AIX

DEFINE CLUSTER for base clusterDEFINE CLUSTER for base cluster

DEFINE AIX for the alternate indexDEFINE AIX for the alternate index

Give base clusters name & alternate keyGive base clusters name & alternate key

Data & Index CI sizesData & Index CI sizes

DEFINE PATHDEFINE PATH Allows specifying of NOUPGRADE pathsAllows specifying of NOUPGRADE paths

BLDINDEXBLDINDEX

Reads primary & alternate key info from baseReads primary & alternate key info from baseclustercluster

Sorts into alternate key sequenceSorts into alternate key sequence

Loads alternate indexLoads alternate index

AIX recommendationsAIX recommendations


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AIX recommendationsAIX recommendations

To process the base cluster in AIXTo process the base cluster in AIX

order, it is better to sort it and useorder, it is better to sort it and use

the SORTOUT filethe SORTOUT file

Remember VSAM processes baseRemember VSAM processes base

clusters directly based on AIX valuesclusters directly based on AIX values Base cluster will need lots of indexBase cluster will need lots of index

buffers for batch processing. Givebuffers for batch processing. GiveBase cluster large BUFFERSPACE onBase cluster large BUFFERSPACE on

DEFINE or ALTERDEFINE or ALTER

AIX and CICSAIX and CICS


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AIX and CICSAIX and CICS

SPHERESPHERE a base cluster and all itsa base cluster and all itsAIXsAIXs related to itrelated to it

RequirementsRequirements Each sphere must be wholly within oneEach sphere must be wholly within one

LSR poolLSR pool

Use Dataset Name SharingUse Dataset Name Sharing In CICS 2.3, add BASE= to FCT entry forIn CICS 2.3, add BASE= to FCT entry for

Base cluster file entryBase cluster file entry

Each related path file entryEach related path file entry

This is automatic in CICS TSThis is automatic in CICS TS

SHR(2) is usually bestSHR(2) is usually best

Make sure your CICS and VSAM serviceMake sure your CICS and VSAM service

is current!is current!

Contacting the presenterContacting the presenter


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Contacting the presenterContacting the presenter

You can contact me by email atYou can contact me by email at

johnm@[email protected]

DanDan JandasJandas website has much ofwebsite has much of

this infothis info http://business.epix.net/~theswamihttp://business.epix.net/~theswami

And, if you want to find me thisAnd, if you want to find me thiseveningevening

Youll find me hereYoull find me here
mailto:[email protected]:[email protected]:[email protected]:[email protected]:[email protected]:[email protected]://business.epix.net/~theswamihttp://business.epix.net/~theswamihttp://business.epix.net/~theswamimailto:[email protected]


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You ll find me hereYou ll find me here

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