DB2 12 A new spin on a successful database

Transcription

1 Presenter: Dan Lohmeier Lead Developer BMC Software Author: Phil Grainger Product Manager BMC Software DB2 12 A new spin on a successful database

2 So, what s new with DB2 12 We ll take a speedy journey through: Performance Performance Management Changes for Applications Scalability Availability Security Utilities How do we get there? And Continuous Delivery I can t cover everything But hold on to your seats! 2

3 Performance

4 Better use of storage CONTIGUOUS bufferpools for in memory tables Improvement on PGSTEAL(NONE) No page chain management Reduces GETPAGE overhead Direct access to row in memory! Automatic overflow area if objects are too large Could save up to 8% cpu From IBM material 4

5 In-memory indexes Index Fast Traverse Block Faster traversal of index pages Storage area separate from bufferpools Default is lesser of 500MB or 20% of allocated bufferpools Usage managed by DB2 DB2 determines which indexes will benefit 5

6 New insert algorithm Insert Algorithm 2 Seen no details from IBM Must be proprietary Up to 20% cpu REDUCTION From IBM material With increased throughput Over 1 MILLION inserts per SECOND Anyone getting close to needing THAT level of performance? 7

7 Performance overview - OLTP Numbers from IBM material 2%-3% cpu reduction Increases to 5%-10% with Index FTB Contiguous bufferpools can improve this even further 8

8 Performance overview Query Numbers from IBM material 0%-20% cpu reduction with older access paths 10%-40% with new access paths Some may even see up to 90% cpu reduction 9

9 Performance Management Changes

10 Dynamic SQL stability Bring advantages of static SQL bind to dynamic SQL Advanced plan management Predictable performance No accidental performance regression 11

11 Dynamic SQL stability Allows dynamic SQL access paths to be retained in the catalog Can EXPLAIN and FREE stabilized plans New SQL matched against stabilized plans before prepare/execute Access path can be read into cache from catalog 12

12 Dynamic SQL stability but No REBIND No PLANMGMT, SWITCH or APREUSE No literal concentration 13

13 Static SQL stability BIND REPLACE of same version doesn t now change LAST USED FREE original or previous Optionally free only if invalid REBIND SWITCH to ORIGINAL As well as PREVIOUS Avoid accidental switch to invalid copy 14

14 RUNSTATS improvements INLINE stats now support RUNSTATS profiles Optimizer can automatically update profiles DSNACCOX recommends RUNSTATS after a profile has been changed Statement cache invalidation Now optional for RUNSTATS (default is DON T) Other utilities ONLY invalidate if an object was in a pending status CLUSTERRATIO calculation improvements Proprietary, as before 15

15 Changes for Applications

16 Overview of selected SQL changes UNICODE columns in EBCDIC tables Piecewise delete DELETE FROM (SELECT * FROM mytab WHERE.. FETCH FIRST 5000 ROWS ONLY) Can intersperse COMMITs in large URs Inclusive/Inclusive for business (bi-)temporal 19

17 Overview of selected SQL changes Global variable extensions LOB and Array global variables Global variables in FETCH, EXECUTE and OPEN statements Procedural SQL enhancements Allowed in Triggers Including looping and conditional control Be careful of new overheads Support for source obfuscation 20

18 Improved MERGE support Multiple MATCHED clauses Additional predicate support DELETE support SIGNAL and IGNORE allowed 21

19 Simpler SQL pagination Data dependent WHERE (LASTNAME, FIRSTNAME) > ( GRAINGER, PHILIP ) Continue fetching after GRAINGER, PHILIP Numeric based SELECT * FROM emp_tab OFFSET 23 ROWS FETCH FIRST 23 ROWS ONLY 22

20 Scalability

21 Addressing partition limits New UTS PBR called UTS PBR Relative Page Number (RPN) UTS PBR RPN Hooray for the TLA Pages are numbered PER PARTITION Eliminates inverse relationship between number of partitions and individual partition size And DSSIZE is now at partition level 7 byte RID (2 for partition, 5 for page number) Up to 1TB partition size Up to 4PB table size (but not finished yet) 256(ish) TRILLION rows per table space Theoretical 64K partitions? 24

22 More on PBR RPN Zparm for system default PAGENUM ABSOLUTE/RELATIVE for DDL Can ALTER this is a pending change Increasing DSSIZE is immediate No reorg needed Decreasing DSSIZE is a pending alter Still requires entire tablespace reorg 25

23 Availability

24 Online Schema enhancements Insert partition ALTER TABLE ADD PARTITION ENDING AT xxx Data distributed between new and old partitions at reorg Be wary of REALLY old classic partitioned tablespaces With truncated limit keys Index compression Column level alters (existing) can become pending alters Zparm for ALWAYS IMMEDIATE or ALWAYS PENDING 28

25 Security

26 Security changes Transfer of ownership Installation/Migration without SYSDADM UNLOAD privilege Long (and CaMeL based) DBRM names 30

27 Utilities

28 Reorg Reorg with only flashcopy now fails if the flash fails UTS PBG Reorg allows row overflow on part level operations New keywords for PBG partition pruning Support for COMPRESSRATIO catalog column Compression ratio at ROW (not page) level Also in Load and Runstats 32

29 Reorg (Cont.) Up to 17% more ziip offload Mapping table changes for PBR RPN Even BNFA Permit Reorg against RO objects Is this really a good idea? Needed for schema changes 33

30 Load Better LOAD REPLACE partition with dummy input, against empty partition Nothing to do, so does nothing! Today, it traverses the entire NPI(s) looking for keys to delete Parallel load support for SHRLEVEL CHANGE against PBG Up to 90% additional ziip offload 34

31 Recovery PIT recovery support for some alters of PBGs Page size, segsize, member cluster and dssize Skip Point In Time recovery for unchanged objects New default behaviour Override with SCOPE(ALL) System level backup for multiple copypools 36

32 Runstats Load and Reorg inline stats support runstats profiles INVALIDATECACHE parameter to force invalidation Remember, default behaviour is now NOT to invalidate Colgroup performance improvements And supported by LOAD PARALLEL inline stats 37

33 Runstats (Cont.) Improved concurrency For MODIFY, COPYTOCOPY and MERGCOPY Against LOAD or REORG Changes to DSNACCOX to avoid more reorgs Solution to reorg problems? CLOB input to DSNUTILV stored procedure Utility statements can be up to 2GB! 38

34 Pause for breath

35 How do we get to DB2 12? Migration from DB2 11

36 Migration requires z196 machine, or higher At least z/os v2.1 DFSMS V2.1 or later RACF V2.1 or later And DB2 11 NFM 41

37 DB2 pre-requisites DB2 11 with fallback SPEs DB2 12 may need more real storage than DB2 11 BSDS supporting 10-byte RBAs No pre DB2 10 bound packages Basic Row Format is deprecated It still works, but can no longer convert objects to BRF 42

38 Single phase migration On your initial arrival at DB2 V12 GA DB2 LVL (121501) Will depend on maintenance applied CATALOG LEVEL(V12R1M500) Will depend on maintenance applied CATMAINT has been run CURRENT FUNCTION LEVEL(V12R1M100) HIGHEST ACTIVATED FUNCTION LEVEL(V12R1M100) HIGHEST POSSIBLE FUNCTION LEVEL(V12R1M501) Will depend on maintenance applied and CATALOG LEVEL -ACTIVATE FUNCTION LEVEL (V12R1M500) Now you are able to use DB2 V12 GA new functionality MODE does not exist CM/ENFM/NFM/CM*/ENFM* 43

39 APPLCOMPAT DSN6SPRM.APPLCOMPAT <system default> V12R1M5nn V12R1M500 V12R1M100 V11R1 V10R1 BIND/REBIND.APPLCOMPAT Explicit APPLCOMPAT <value> Allow DSNZPARM value Do not include on bind/rebind How should this package behave Allow it to exploit Do not allow it to exploit Business applications DB2/ISV products and tools 44

40 Continuous Delivery

41 Continuous Delivery DB2 LVL (1215nn) What PTF s do you have applied CATALOG LEVEL(V12R1M5nn) What CATMAINT processes have been run CURRENT FUNCTION LEVEL(V12R1Mnnn) /(V12R1Mnnn*) -ACTIVATE FUNCTION LEVEL (V12R1Mnnn) Can go up or down* HIGHEST ACTIVATED FUNCTION LEVEL(V12R1Mnnn) HIGHEST POSSIBLE FUNCTION LEVEL(V12R1Mnnn) Will depend on maintenance applied and CATALOG LEVEL 46

42 Continuous Delivery To get to even newer functions, we just -ACTIVATE FUNCTION LEVEL (V12R1Mnnn) as appropriate -DISPLAY GROUP will tell us where we are and where we ve been There is also a TEST option for ACTIVATE To ensure that we CAN activate a new function level i.e., all the pieces are in place AND yes, we can activate backwards Function Level 502 (PI95511 (UI55093) and PI95996 (UI55098)) are available (as of 4/30/18). 47

43 Continuous Delivery DSN7100I *DEJM DSN7GCMD *** BEGIN DISPLAY OF GROUP(...) CATALOG LEVEL(V12R1M500) CURRENT FUNCTION LEVEL(V12R1M500) HIGHEST ACTIVATED FUNCTION LEVEL(V12R1M500) HIGHEST POSSIBLE FUNCTION LEVEL(V12R1M501) PROTOCOL LEVEL(2) GROUP ATTACH NAME(...) DB2 SUB DB2 SYSTEM IRLM MEMBER ID SYS CMDPREF STATUS LVL NAME SUBSYS IRLMPROC DEJM *DEJM ACTIVE DB2B IEJM DEJMIRLM SPT01 INLINE LENGTH: *** END DISPLAY OF GROUP(...) DSN9022I *DEJM DSN7GCMD 'DISPLAY GROUP ' NORMAL COMPLETION *** 48

44 Continuous Delivery DSN7100I *DMC1 DSN7GCMD *** BEGIN DISPLAY OF GROUP(DSNDMC ) CATALOG LEVEL(V12R1M500) CURRENT FUNCTION LEVEL(V12R1M501) HIGHEST ACTIVATED FUNCTION LEVEL(V12R1M501) HIGHEST POSSIBLE FUNCTION LEVEL(V12R1M501) PROTOCOL LEVEL(2) GROUP ATTACH NAME(DMC ) DB2 SUB DB2 SYSTEM IRLM MEMBER ID SYS CMDPREF STATUS LVL NAME SUBSYS IRLMPROC DMC1 1 DMC1 *DMC1 ACTIVE DB2B IMC1 DMC1IRLM DMC2 2 DMC2 *DMC2 ACTIVE DB2A IMC2 DMC2IRLM DB2 PARALLEL PARALLEL MEMBER COORDINATOR ASSISTANT DMC1 NO NO DMC2 NO NO DISPLAY SUBGROUP ATTACH INFORMATION FOR GROUP ATTACH DMC 49

45 APPLCOMPAT DSN6SPRM.APPLCOMPAT <system default> V12R1M5nn V12R1M500 V12R1M100 V11R1 V10R1 BIND/REBIND.APPLCOMPAT Explicit APPLCOMPAT <value> Allow DSNZPARM value Do not include on bind/rebind How should this package behave Allow it to exploit Do not allow it to exploit Business applications DB2/ISV products and tools 50

46 Questions?

47 Vielen Dank! Thank You!