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IBM Global ServicesIBM Global Technology Services
What’s New in DB2 9 for z/OS
2009. 05. 14
Soohee Lee([email protected])시스템 서비스 사업본부IBM Global Technology Services
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Agenda
DB2 9 for z/OS
Synergy with System z
Scalability
Availability
Data sharing
Application Enhancements
Utilities
Performance
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DB2 9 for z/OS
SOA Enablement
pureXML
Optimistic locking for WebSphere
LOB performance, usability
WorkloadConsolidation
More online schema changes
Online REBUILD INDEX
Parallel Sysplex clustering improvements
SimplificationReduced TCO
Index compressionPartition By Growth tablesCloned tables
DynamicWarehousing
Many SQL improvements
New built-in OLAP expressions
Histogram statistics
Optimization Server Center
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Synergy with System z
DB2 9 for z/OS
Synergy with System z Scalability
Availability
Data sharing
Application Enhancements
Utilities
Performance
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Faster CPU, more CPU, more memory•50% more n-way performance “on average”•62% more uniprocessor performance•70% more server capacity (54->64 CPUs)•Up to 64 CPUs, z/OS 1.9 needed for 64-way in a single LPAR•Up to 1.5TB, z/OS 1.8 needed for > 256G in a single LPAR
Infiniband Coupling Facility linksNew OSA-Express3, 10 GbE for faster remote appsHiperDispatchHardware Decimal Floating Point facility1MB page size (DB2 X plans to exploit)50+ instructions added to improve compiled code efficiency (DB2 X plans to use)
IBM System z10 Benefits for DB2
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portions of DB2 for z/OS V8 and DB2 9(blue) workloads may benefit from zIIP*:
ERP, CRM, Business Intelligence or other enterprise applications
• Via DRDA over a TCP/IP connection (enclave SRB, not stored procedure or UDFs)
• DB2 9 for z/OS Remote native SQL procedure
• DB2 9 XML paring
DB2 & IBM zIIP value
New Specialty Engine
Data warehousing application*: Large parallel SQL queries DB2 9 higher percentage of parallel queries eligible for
zIIP DB2 utilities LOAD, REORG & REBUILD (maintaining index
structures)zIIP allows a program working with z/OS to have all or a portion of its enclave Service Request Block(SRB) work direction to zIIP. Above types of DB2 work are those running in enclave SRBs, of which portions can be sent to zIIP.
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zIIP Software
• z/OS V1R8 기반 ( 운영체제 기능에 기본 내장 )
• z/OS V1R6-V1R7 FMIDs : R6 – JBB77S9 / R7 – JBB772SSPE for SDSF (APAR PK18215) / RMF (APAR OA13499)
• DB2 V9.1 기반 ( 소프트웨어 기능에 기본 내장 )
• DB2 V8 DRDA : PK18454Utilities : PK19920 Parallel Query / Star Join – PK19921
zIIP projection
• SYS1.PARMLIB (IEAOPTxx) : PROJECTCPU=YES
• determine how much work can be offloaded to the zIIP (without zIIP)
zIIP Enabling
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DB2 V9.1 for z/OS
Synergy with System z
Scalability Availability
Data Sharing
Application Enhancements
Utilities
Performance
Scalability
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DB2 9 64 bit Evolution (Virtual Storage Relief)
EDMPOOL Changes:•V8 - DBD storage moved above 2GB bar.•DB2 9 - SKCT, SKPT some CT, PT storage moved aboved 2GB bar.•DB2 9 approx. 60% reduction in below-the-bar storage EDMPOOL size observed for lab workloads.
Other changes : •Some storage acquired for distributed application moved above 2GB bar.•Control blocks for table spaces and RTS move aboved the bar.•Control block structures for dynamic SQL-related storage
Virtual Storage Constraint in an important issue for many DB2 customers.
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Automated memory monitoring
Built-in monitor runs from startup to shutdown and checks the health of the system at one-minute intervals.
DBM1 storage below the bar is monitored for critical storage increases.
•If the DBM1 storage below the bar reaches specific thresholds of 88, 92, 96, or 98 percent
•Then issue messages (DSNV508I, DSNV510I, DSNV511I, and DSNV512I)
• Report current DBM1 storage consumption and indicate the agents that are consuming the most storage.
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64-bit DDF - Shared Private Storage with DBM1
DDF address space runs in 64-bit addressing mode
• Shared 64-bit memory object avoids cross memory moves between DBM1 and DDF and improve performance.
Shared memory : new virtual storage type allowing multiple address spaces to share storage.
Similar to ECSA - always addressable, avoids XM moves.
Different from ECSA - only available to those address spaces registering with z/OS to shared this storage.
Reduces data formatting and data movement.
Reduces virtual storage•It exists once, instead of in each address space
•Set by HVSHARE in PARMLIB(IEASYSxx)•DISPLAY VIRTSTOR,HVSHARE
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WLM assisted Buffer Pool management WLM-assisted buffer pool management
• ALTER BUFFERPOOL () AUTOSIZE(YES)
• z/OS 1.8
• DB2 registers BP to WLM and reports synch read I/O delays to WLM
• DB2 periodically reports BP hit stats to WLM
• WLM projects effect of adjusting BP size on workload performance goals
•WLM drives DB2 exit to adjust size if appropriate
DB2 9 restricts to +/- 25%
BP0
DBM1 WLMData Collection
DB2 Periodic Report
Buffer Pool SizesHit Ratio for Random Reads
1 Plots size and hit ratio over time.2 Projects effects of changing the size
Bufferpool Adjustment+ - 25%
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NOT LOGGED Table spaces ALTER / CREATE TABLESPACE as NOT LOGGED
• ALTER not allowed if in same UOW with an update to the table space Reduce logging in situations where is not required. Turn ON/OFF logging during the heavy insert or update activity. Effects the UNDO / REDO records
• Control information is still logged. A Unit of Recovery (UR) is still created Indexes, LOB and XML inherit the logging attribute of the base
LOG YES is a synonym for LOGGED
LOG NO is a synonym for NOT LOGGED
Recommendation: Don’t sacrifice recovery for minor performance gain.
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Universal Table Spaces Combination of segmented with partitioning options
• improved space management• improved mass delete performance
2-types of partitioning• Partition by RANGE (PBR)
Key range partitioning that we’ve always had• Partition by GROWTH (PBG)
New partitions are added as data grows Single table only (1 TABLE / 1 TABLESPACE) DROP / CREATE to migrate existing page sets Simple table spaces can not be created
• Default table space is now Segmented
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Universal Table Spaces (PBR & PBG) UTS - Partition by range (PBR)
• This is no difference to Version 8 (and prior) partitioning• A UTS PBR is created just like a normal partitioned table space• But with a SEGSIZE clause
UTS - Partition by growth (PBG)•Starts off as one partition table space•As data is inserted/loaded the partition will fill up•When it is full, another partition is automatically created
No -904No partitioning key
•You specify the limit to the number of partitions on the CREATE/ALTER table space statement
MAXPARTITIONS
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Regardless of the order of columns in a CREATE TABLE statement
Physically, the fixed length columns will be first Followed by the variable length ones
• This is known as Reordered Row Format (RRF)• As opposed to Basic Row Format (BRF)
Reordered Row Format (RRF) The performance of RRF is SO much better than BRF This is NOT optional Once you are in New Function Mode this is the only way
• For every CREATE TABLE• And after every REORG or LOAD REPLACE
Reduce the impact and overhead of processing variable-length columns.
Variable-Length Column Improvements
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Indexing Enhancements Larger index pages
•8K /16K /32K page•Fewer page splits for long keys•More key values per page
Index compression •Reduce the storage consumed by large index (like as DW Application)•CREATE/ALTER INDEX COMRESS YES/NO•No compression dictionaries•Only compress the data in leaf pages•Data is compressed to 4K pages on disk•32K/16K/8K pages results in up to 8x/4x/2x disk savings
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Indexing Enhancements Asymmetric Index Page Splits
Index split roughly 50/50 (prior to DB2 9)
Sequential inserts into the middle of an index resulted in some pages with 50% free space
Asymmetric Index page split in DB2 9
New algorithm dynamically accommodates a varying pattern of inserts
Improve space utilization and reduce contention that results from frequent page splits in a index with sequential insert patterns
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Indexing Enhancements RANDOM index key
• Avoid hot spots with multiple processes inserting sequential keys
• Reduce contention of index page P-lock
•Trade-off between contention relief and additional Getpage, read/write I/O
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Native SQL Procedure Run entirely within DB2 and do not require a WLM stored procedure AS
Eliminates the cross address space overhead between the DBM1 and WLM stored procedure AS as well as the round-trip between Workload Manager and DBM1
eligible for ZIIP if invoked from DRDA/TCPIP connectionsNative SQL Procedural Language
•Fully integrated into the DB2 engine
•Eliminates generated C code and compilation
• An SQL procedure created without FENCED or EXTERNAL is a native SQL procedure
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DB2 Trace Filtering New filtering capabilities for –START TRACE that INCLUDE or EXCLUDE base
d on these keywords:•USERID -- client useridWRKSTN -- client workstation nameAPPNAME -- client application namePKGLOC -- package LOCATION namePKGCOL -- package COLLECTION namePKGPROG -- PACKAGE nameCONNID -- connection IDCORRID -- correlation ID
In V8 , only PLAN, AUTHID, LOCATION
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DB2 V9.1 for z/OS
Synergy with System z
Scalability
Availability Data Sharing
Application Enhancements
Utilities
Performance
Availability
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CLONE TablesFast way to replace table contentsEliminate outage for LOAD REPLACECLONE are created with an ALTER statement
•ALTER TABLE ADD CLONE clone-table-name•UTS only
A CLONE inherits ALL of the attributes of the base table•Including all indexes, constraints, triggers•Structures ONLY - not data
CLONE has a different INSTANCE number to the base object. •VCAT.DSNDBC.ddd.ppp.I0002.Annn
CLONE and base table can be used independently•For SQL•For Utilities (new CLONE keyword, except RUNSTATS)
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CLONE TablesEXCHANGE DATA BETWEEN syntax
•Drain & switch
•DB2 switches the instance numbers in the catalog
•This is FASTVery like a switch phase
Before EXCHANGE
After EXCHANGEBase-table clone-table
Base-table clone-table
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Recovery to point in time with consistencyPrior to DB2 V8, if point-in time recovery, consistency is not ensured. (If the point is not consistency point)
In DB V9 , Full data consistency Occurs for TOLOGPOINT & TORBA - not for TOCOPYUncommitted URs will be rolled backReduce need for QUIESCE pointsAfter LOGAPPLY , new 2 phase (LOGSCR,LOGUNDO)
LOGSCR : Analyzes log records and constructs information about in-flight, indoubt, inabort, and postponed abort units of recovery.LOGUNDO : Rolls back any uncommitted changes that the active units of recovery made to the recovered objects.
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APPEND Table
CREATE / ALTER TABLE APPEND YES/NO
Ignore clustering during SQL inserts and online LOAD processing
Rows are appended at the end of the table or appropriate partition
You can insert or online LOAD your data quickly and regain the clustering order later by running REORG.
Benefit !!:
•Maximizes performance for “INSERT at end”
•Avoids overhead of attempting to preserve clustering sequence
TABLE
INSERT or
Online LOAD
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REFRESH for EARLY code Modify early code without IPL New command
• REFRESH DB2,EARLY• Member-scope•The command is rejected if the DB2 subsystem is already active. •The EARLY code can only be properly updated when DB2 is not active
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RENAME INDEX & RENAME COLUMN Change object characteristics without need to drop and recreate the object.
RENAME INDEX • RENAME INDEX source-index-name TO new-index-name• Does not change OBID• Plan and package will not be invalidated
RENAME COLUMN• ALTER TABLE tablename RENAME COLUMN old-col TO new-col• Invalidation of any plan or package that is dependent on the table• Auto Rebinding occurs
• Scenario1 : no reference the renamed column Rebind will be successful
• Scenario2 : reference the renamed columnRebind will not be successfulMust modify, recompile and rebind your application
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Log truncation by timestamp Conditional restart log truncation by timestamp
New parameters on CRESTART CREATE ENDTIME SYSPITRT (SYSTEM LEVEL RECOVERY MODE)
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Ability to cancel “DB command” Ability to cancel “database command” that have been issued from the console.
•-STOP DB(DSN0170) SP(TESTIMP*) command with some other thread
• -DIS THD(*) TYPE(SYSTEM)
•You can issue, -CANCEL THD(93) for command or system agent.
• After CANCEL, You can issue -START DB command to change status STOPP to RW.
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Migration and Fallback Path With DB2 9 , you can always drop back to the previous stage Cannot fallback to V8 after entry to DB2 9 (ENFM), but can fallback to DB2 9 (CM*)
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Data Sharing
DB2 V9.1 for z/OS
Synergy with System z
Scalability
Availability
Data Sharing Application Enhancements
Utilities
Performance
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Data Sharing EnhancementLog latch contention reliefRestart performance enhancement
•Reduced impact of retained lock - Allowing table level retained locks
•Open data sets ahead of log applyRemove GBP-dependency at object level by command
•ACCESS DB MODE(NGBPDEP)
•Typical usage would be before batch runOpen dataset ahead of use via command
•Available to pre-open or prime the data set
•ACCESS DB MODE(OPEN) [PART]Auto-recover GRECP/LPL objects on group restart
•Useful in disaster recovery or GDPS scenariosBalance group attach connections across multiple members on same LPAR (round-robin basis)
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SQL
DB2 V9.1 for z/OS
Synergy with System z
Scalability
Availability
Data Sharing
Application Enhancements Utilities
Performance
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MERGE“Upsert”
•A combination of UPDATE and INSERT, MERGE is a single SQL operation•Single row or multi-row
If a row matches the ON condition it is updated,Otherwise it is insertedProvides better performance, less interaction across the network, less DB2 and application interaction, and less SQL to code.
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SELECT FROM UPDATE/DELETE/MERGE
Used to determine the values before or after records•FINAL TABLE : select from rows after update•OLD TABLE : select from row before update
•INCLUDE clause •include a new column to the result table but not add the column to the target table.
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FETCH FIRST/ ORDER BY in Subselect
FETCH FIRST and ORDER BY clauses are now allowed in subselects. In this example both clauses are used in the subselect as a way to select the top 10 rows from table T1 as ordered by columns C2 and C1.
INSERT INTO T2
(SELECT C1, C2, C3 FROM T1 FETCH FIRST 10 ROWS ONLY ORDER BY C2, C1);
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SKIP LOCK DATA in SELECTSKIP LOCK DATA in SELECT
•Rows with incompatible locks by other transactions are skipped
X X Xdata data data data data data data data
SQL
• Page or Row lock only• Reduce lock contention and improve performance
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TRUNCATE Very quickly delete all rows from a table
• Simple , Segmented, Partitioned , Universal Tablespaces• IGNORE delete triggers ,deletes the data WITHOUT firing delete triggers• Table level deletion (LOAD REPLACE works on tablespace level)• IMMEDIATE option - operation cannot rolled back
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INTERSECT / EXCEPTIntersect – Returns the records that two result sets have in common
•Frequently used in ‘find the duplicates query’•Rows from either result set that do not match are excluded.
Except – Returns the records that are members of one result set that are not members of the other Requirement
•Both result sets must have the same column structure.
RS2RS1
RS2RS1
Intersect
RS1 RS2
Except
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Index on Expression Simple indexes can contain concatenated column
CREATE INDEX totalPay on W2_TABLE(salary,bonus)
Index on expression
•Value of the index has been transformed
•Optimizer can use this index
•Query performance can be enhanced
•Evaluate during insertion time or during index rebuildCREATE INDEX totalPay on
W2_TABLE(salary+bonus)
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Built-in Functions (RANK, DENSE_RANK) RANK
Generates a row number defining the rank as 1 plus the number of rows that precede the row.If two or more rows are not distinct with respect to the ordering, there will be one or more gaps in the sequential rank numbering. Also referred to as Olympic Ranking.
DENSE_RANKSimilar to RANK but ensures there are no gaps.
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Built-in Functions (RANK, DENSE_RANK)
SELECT SMALLINT(DENSE_RANK() OVER (ORDER BY score DESC)) AS DENSE_RANK,athlete, event, score FROM scores;
SELECT SMALLINT(RANK() OVER (ORDER BY score DESC)) as RANK,athlete, event, score FROM scores;
RANK
DENSE_RANK
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Built-in Functions (ROW_NUMBER)
ROW_NUMBER•Creates a sequential row number that is computed for each row starting with 1. •No number skipping.
SELECT SMALLINT(ROW_NUMBER() OVER (ORDER BY score DESC)) AS ROW_NUMBER, athlete, score FROM scores ORDER score DESC;
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Time Scalar Functions
TIMESTAMPADD(interval, number, timestamp)•Returns the result of adding the specified number of the specified interval to the specified timestamp•Add 1 year to the current timestampSELECT TIMESTAMPADD(256,40,TIMESTAMP('1965-07-27-15.30.00')) FROM SYSIBM.SYSDUMMY1;•Returns a value ’2005-07-27-15.30.00.000000’.•Interval values are 256=years, 128=quarters, 64=months, etc
TIMESTAMP_ISO(expression)•Returns a timestamp based on a date, a time, or a timestamp expression.SELECT TIMESTAMP_ISO(DATE(‘1992-02-19’)) FROM SYSIBM.SYSDUMMY1;•Returns a value ‘1992-02-19-00.00.00.000000’
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Real-Time Statistics EvolutionReal Time Statistics (RTS) have been collected automatically since V7DB2 9 moves RTS into the Catalog & externalizes the information automatically
•DSNDB06.SYSRTSTSSYSIBM.SYSTABLESPACESTATSSYSIBM.SYSINDEXSPACESTATS
•During ENFM processing, the data is moved from user-defined tables to the new catalog tables•Drop user-defined tables after ENFM
Gather information about indexes that are used / not used•SYSINDEXSPACESTATS.LASTUSED•"Used", as defined by DB2 is the following:
As an access path for query or fetch.For searched UPDATE / DELETE SQL statement.As a primary index for referential integrity.To support foreign key access.
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Plan StabilityNew function of DB2 9 (PK52523)
•Protects customers against access path regression•Allows for a “safe” way to REBIND (fall back)•Available even in DB2 9 (CM) as it can benefit migration and fallback•Strongly recommended•Make sure that the pre-conditioning APAR for Plan Stability (PK52522) is applied on all V8 (NFM) systems
What is the problem?•REBINDs can cause access path changes•Most of the time, this improves query performance …•… But when it doesn’t
No easy way to undo the REBINDCan lead to a lot of grief to our customers and to IBM
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Plan Stability...
At REBIND, save old copies of packages•Catalog tables•Directory
Two flavors•BASIC and EXTENDED•Controlled by new ZPARM PLANMGMT•Default is OFF•Also supported as REBIND options
REBIND PACKAGE …•PLANMGMT(BASIC)
2 copies: Current and Previous•PLANMGMT(EXTENDED)
3 copies: Current, Previous, Original
Most bind options can be changed at REBIND
•But a few must be the same
REBIND PACKAGE …•SWITCH(PREVIOUS)
Switch between current & previous
•SWITCH(ORIGINAL)Switch between current & original
FREE PACKAGE …•PLANMGMTSCOPE(ALL) – Free package completely•PLANMGMTSCOPE(INACTIVE) – Free all old copies
Invalidation and Auto rebind•Each copy invalidated separately•Auto rebind replaces only the current copy , previous and original are not affected
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Plan Stability... REBIND ... PLANMGMT(BASIC) REBIND ... SWITCH(PREVIOUS)
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Plan Stability... REBIND ... PLANMGMT(EXTENED) REBIND ... SWITCH(ORIGINAL)
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Plan Stability... Sample Strategy for Migration using Plan StabilityMigration strategy with Plan Stability
•Before migrating to DB2 9 (CM), ensure V8 plan table information is available•On migration to DB2 9 (CM), set ZPARM PLANMGNT to EXTENDED
Objective: Make sure that the V8 version of package is kept as the original in case a fallback to DB2 V8 is requiredRestriction: EXTENDED means that DB2 always keeps 3 versions of the package (even if they are the same). Watch out for SPT01 growth (limit is still 64GB with DB2 9).
•Delay rebind on DB2 9 (CM) until running stableDo not rebind on DB2 9 (CM) until RUNSTATS has been runMake sure new ZPARM STATCLUS=ENHANCED (Default)Introduces major change to CLUSTERRATIO calculation in DB2 9 and introduction of new statistic Data Repetition Factor (DRF)
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Plan Stability... Sample Strategy for Migration using Plan Stability REBIND in DB2 9 (CM)
• DB2 now stores 3 versions of the package• Initial REBIND
Current version = DB2 9 version Previous version = Original version = V8 version If needed because of V9 access path regression, use REBIND
PACKAGE …SWITCH(PREVIOUS) to fallback to the V8 version• Subsequent REBINDs
Current version = “New” DB2 9 version Previous version = Latest DB2 9 version Original version = V8 version Use REBIND PACKAGE … SWITCH(PREVIOUS) to fallback to the
previous V9 version
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Plan Stability... Sample Strategy for Migration using Plan Stability
In case of fallback to DB2 V8, before falling back to V8• Use REBIND PACKAGE … SWITCH(ORIGINAL) to fall back to
original version of package (V8 version)
In the future, to establish a new original version e.g to move forward to the version after DB2 9
• Use FREE PACKAGE … PLANMGMTSCOPE(INACTIVE) to free off the original (will also free off the previous version)
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Two ways to store XML in a Databases
deptID … deptdoc
“PR27” … <dept> …
<emp>…</emp>
</dept>
… … …
DB2 Storage
Competitors DB2 9 Pure XML
create table dept (deptID char(8),…, deptdoc xml);
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Pure XML in DB2 9
create table dept (deptID char(8),…, deptdoc xml); XML data is stored in XML-typed
columns in tables
• XML is stored in a parsed hierarchical format
• Relational columns are stored in relational format
• The XML table space inherits the base table attributes
SQL/XML constructor functions and XPath support
XML Indexing
• improve the efficiency of queries on XML
Improve XML performance
deptID … deptdoc
“PR27” … <dept> …
<emp>…</emp>
</dept>
… … …
DB2 Storage
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Utilities
DB2 V9.1 for z/OS
Synergy with System z
Scalability
Availability
Data Sharing
Application Enhancements
Utilities Performance
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DB2 9 Utilities Performance Improvement
CPU reduction in LOAD, REORG and REBUILD Reductions mostly due to improved index processing (* with exceptions)
10 to 20% in Image Copy (* even with forced CHECKPAGE YES) 5 to 30% in load, Reorg, Reorg Partition, Rebuild Index
• Except REORG TABLESPACE SHR CHG PART with NPIs 20 to 40% in Load 20 to 60% in Check Index 35% in Load Partition 30 to 40% in Runstats Index 40 to 50% in Reorg Index Up to 70% in Load Replace Partition with dummy input
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REORG Enhancement
Elimination of BUILD2 phase
•REORG TS PART SHRLEVEL CHANGE
•NPI also shadowed
•NPI implicitly reorged
•Improved availability But concurrent REORGs at part level for same tablespace not permitted
REORG parallelism for UNLOAD, RELOAD, LOG phases
• Parallel uload & load of partitions
• Separate concurrent jobs not required
• Improve performance
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REORG Enhancement Automatic display of blocking claimers for REORG
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Online REBUILD INDEX
REBUILD INDEX SHRLEVEL CHANGE Great for building new non-unique indexes or when index is in RBDP
Do not use REBUILD INDEX to move the index to a new location.
• use REORG INDEX to move volume
• use REBUILD INDEX SHR CHG to fix a broken or restricted index, or to build an index after DEFER.
Tables space must be in LOGGED state (new log phase) SHRLEVEL CHANGE is not well suited for unique indexes and concurrent DML
Inserts and updates of the index will fail with a resource unavailable (-904) because uniqueness checking cannot be done while the index is in RBDP.
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Online CHECK DATA
CHANGE CHECK DATA works on a copy of the data and indexes (shadows) Applications can read from and write to the index, table space, or partition that is to be checked.
Improve availability
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UNLOAD SKIP LOCKED DATA
Skipping locked rows during UNLOAD• UNLOAD SHRLEVEL CHANGE ISOLATION CS & SKIP LOCKED DATA • With SKIP LOCKED DATA, the UNLOAD utility can skip rows on which incompatible locks are held by other transactions. • Reduce lock contention, improve performance
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MODIFY RECOVERY
MODIFY RECOVERY simplification and safety You can specify
• What you want to delete : DELETE keyword • What you want to keep : RETAINE keyword (new in V9) • Improve usability
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RECOVER Enhancement RECOVER RESTOREBEFORE(RBA OR LRSN)
•When lost the least recent image copy (with TORBA or TOLOGPOINT)
•Tell db2 to not try to allocate the lost image copy but to work with older copy
Displaying progress of RECOVER (During LOGAPPLY phase)
-DISPLAY UTILITY result with a new message DSNU116I
Indicates the range of the log that needs to be applied
Show the progress that has been made up to the last commit and the elapsed time since the start of the log apply phase of the recovery.
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Julian Data and Time in Utility Output
Julian date and time stamp(local time) in utility output•Easier to analyze utility runs ,•Include timestamp with message number in SYSPRINT
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Performance
DB2 V9.1 for z/OS
Synergy with System z
Scalability
Availability
Data Sharing
Application Enhancements
Utilities
Performance
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DB2 9 for z/OS Performance Overview
Your situation will vary.
Z800 and z900 expect +5% to +10% CPU
DB2 9 z9 and z990 performance plan example
Utilities
Histogram statistics
REBIND
DSNZPARMs
DB design adjustments
Index Improvements
Application changes
Native SQL procedures
SQL adjustments
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DB2 9 for z/OS Performance Overview
Significant CPU time reduction in most utilities
Synergy with new hardware : zIIP, MIDAW, DS8000,...
Performance / Scalability Enhancements
• Especially Insert, Update & Delete
Query / Access Path Performance Enhancements
Other performance enhancements : LOB, varchar, native SQL procedure, index compression
Improve virtual storage usage below 2GB DBM1