Getting Started with Exadata & Smart Scan

Transcription

1 Getting Started with Exadata & Smart Scan Aman Sharma Aman Sharma

2 Who Am I? Aman Sharma About 12+ years using Oracle Database Oracle ACE Frequent Contributor to OTN Database forum(aman.) Oracle Certified Sun Certified Member - AIOUG,IOUG Member - AIOUG North India Chapter team Twitter * Oracle Blog : * amansharma@aristadba.com Aman Sharma-OTNYatra2015 2

3 What We Shall Talk About Exadata Introduction Exadata Hardware & Network Overview Exadata Software Overview Exadata Key Features Smart Scan Aman Sharma-OTNYatra2015 3

4 A Typical Database Server Setup Aman Sharma-OTNYatra2015 4

5 RAC Database Server Setup Aman Sharma-OTNYatra2015 5

6 So What Can Go Wrong? Aman Sharma-OTNYatra2015 6

7 DBA s Life Can Be Hard! Users/ Developer Manager DBA Aman Sharma-OTNYatra2015 7

8 Say Hello To Exadata Engineered machine catering both OLTP and DSS workloads Platform for Database Cloud Extreme Performance & High Availability Well balanced platform eliminating bottlenecks Robust yet secure & easy to setup and implement Aman Sharma-OTNYatra2015 8

9 Evolution of Exadata Technology Exadata Model Year Storage(TB) Flash(TB) CPU(Cores) Memory(TB) V NIL V X X X Aman Sharma-OTNYatra2015 9

10 Exadata-A Sneak Peak Inside Image courtesy-google Images Aman Sharma-OTNYatra

11 Exadata(X4-2) Available Configurations Aman Sharma-OTNYatra

12 Exadata-Key Features Smart Scan Hybrid Columnar Compression (HCC) Infiniband Network Smart Flash Cache Storage Indexes IORM Aman Sharma-OTNYatra

13 Exadata- Hardware& Network introduction using Quarter RAC Database Server 01 Database Server Port IB1 36 Port IB2 Aman Sharma-OTNYatra

14 Client Access 1GbE-Client Access ILOM Ethernet Switch ILOM Mgmt Access IB3(Spine) Mgmt Access Database Server 01 IB1(Leaf) IB2(Leaf) 10GbE-Client Access Aman Sharma-OTNYatra

15 Exadata-Software Overview DB01 DB02 ORCL1 +ASM1 ORCL2 +ASM2 LIBCELL LIBCELL idb MS RS MS RS MS RS CELLSRV CELLSRV CELLSRV Aman Sharma-OTNYatra

16 Smart(Storage) Scan Smart Scan Hybrid Columnar Compression (HCC) Infiniband Network Smart Flash Cache Storage Indexes IORM Aman Sharma-OTNYatra

17 Smart Scan/Data Offloading Data Offloading makes Exadata magical Offloading is Work is offloaded to the Exadata storage(cells) Not related to just SQL statement execution Going to optimize others operations i.e. Backups also Smart SCAN Is related specifically to SQL statement processing Works for Table/Index Scans, Joins Uses the idb protocol Does NOT work all the time Is NOT an optimizer feature Aman Sharma-OTNYatra

18 Smart Scan-From A Little Closer Smart Scan works for Column Offloading Predicate Offloading Joins(using Bloom Filter) Data access must use Direct-Path Read To have Smart Scan enabled Database must have set CELL_OFFLOAD_PROCESSING=TRUE Disk Group must have set CELL.SMART_SCAN_CAPABLE=TRUE(FALSE) To display Smart Scan in the execution plan, set CELL_OFFLOAD_PLAN_DISPLAY=AUTO/ALWAYS/NEVER Aman Sharma-OTNYatra

19 Smart Scan-When It Doesn t Work On a Clustered table On an Index Organized Table LOB/LONG Column is selected More than 255 columns are referenced in the query No predicate clause or column filtering is used <<partial list>> Aman Sharma-OTNYatra

20 Smart Scan- Example 1 SQL> select count(*) from employees where deptartment = SALES'; COUNT(*) Elapsed: 00:00:02.14 Execution Plan Plan hash value: Id Operation Name Rows Bytes Cost (%CPU) SELECT STATEMENT (1) 1 SORT AGGREGATE 1 7 * 2 TABLE ACCESS STORAGE FULL EMPLOYEES 255K 998K 3136 (1) Predicate Information (identified by operation id): storage( DEPARTMENT"= SALES') filter( DEPARTMENT"= SALES') Aman Sharma-OTNYatra

21 Smart Scan-Going Beyond Execution Plans SQL> SELECT s.name, m.value/1024/1024 MB FROM V$SYSSTAT s, V$MYSTAT m 2 WHERE s.statistic# = m.statistic# AND 3 (s.name LIKE 'physical%total bytes' OR s.name LIKE 'cell phys%' 4 OR s.name LIKE 'cell IO%'); NAME MB physical read total bytes physical write total bytes 0 cell physical IO interconnect bytes cell physical IO bytes saved during optimized file creation 0 cell physical IO bytes saved during optimized RMAN file restore 0 cell physical IO bytes eligible for predicate offload cell physical IO bytes saved by storage index 0 cell physical IO bytes sent directly to DB node to balance CPU 0 cell physical IO interconnect bytes returned by smart scan cell IO uncompressed bytes rows selected. Elapsed: 00:00:00.17 Aman Sharma-OTNYatra

22 Smart Scan-Example 2 SQL> select count(*) from employees where deptartment = SALES'; COUNT(*) Elapsed: 00:00:06.04 Execution Plan Plan hash value: Id Operation Name Rows Bytes Cost (%CPU) SELECT STATEMENT (1) 1 SORT AGGREGATE 1 7 * 2 TABLE ACCESS STORAGE FULL EMPLOYEES 255K 998K 3136 (1) Predicate Information (identified by operation id): storage( DEPARTMENT"= SALES') filter( DEPARTMENT"= SALES') Aman Sharma-OTNYatra

23 But Is Smart Scan Really Helping? SQL> SELECT s.name, m.value/1024/1024 MB FROM V$SYSSTAT s, V$MYSTAT m 2 WHERE s.statistic# = m.statistic# AND 3 (s.name LIKE 'physical%total bytes' OR s.name LIKE 'cell phys%' 4 OR s.name LIKE 'cell IO%'); NAME MB physical read total bytes physical write total bytes 0 cell physical IO interconnect bytes cell physical IO bytes saved during optimized file creation 0 cell physical IO bytes saved during optimized RMAN file restore 0 cell physical IO bytes eligible for predicate offload cell physical IO bytes saved by storage index 0 cell physical IO bytes sent directly to DB node to balance CPU 0 cell physical IO interconnect bytes returned by smart scan cell IO uncompressed bytes rows selected. Elapsed: 00:00:00.17 Aman Sharma-OTNYatra

24 When using Smart Scan, Look For Transactions happening over the buffers thus resulting in dirty buffers Dynamic Sampling Migration of rows or Chained rows Storage Cell Servers CPU s are more busy than DB Servers If the required data is already in the buffer cache Aman Sharma-OTNYatra

25 Smart Scan Related Metrics & Wait Events For Wait Events SELECT DISTINCT event, total_waits, time_waited/100 wait_secs, average_wait/100 avg_wait_secs FROM V$SESSION_EVENT e, V$MYSTAT s WHERE event LIKE 'cell%' AND e.sid = s.sid; For Statistics SELECT s.name, m.value/1024/1024 MB FROM V$SYSSTAT s, V$MYSTAT m WHERE s.statistic# = m.statistic# AND (s.name LIKE 'physical%total bytes' OR s.name LIKE 'cell phys%' OR s.name LIKE 'cell IO%'); Aman Sharma-OTNYatra

26 Exadata-Deployment & Installation Four Step Phase Pre-Installation Uses Oracle Exadata Deployment Assistant(OEDA) Customer side task Installation, Configuration & Deployment Uses OneCommand Oracle Advanced Customer Support (ACS) handles it Additional(Misc.) Configuration For example, deploying EM Cloud Control Customer/ACS Post-Installation Monitoring & maintaining of the Exadata machine Customer/ACS Aman Sharma-OTNYatra

27 OneCommand Latest version available at MOS# Used by the Advanced Customer Support engineers Uses a series of the steps to configure the Exadata machine Executes required configuration steps automatically Customizable Aman Sharma-OTNYatra

28 Oracle Exadata Machine Storage Server- System Accounts CELLADMIN user Uses CELLCLI utility to do the administration tasks Can manage storage components of the storage server Default password- welcome CELLMONITOR user For monitoring only Doesn t have any administrative privileges Default password- welcome ROOT user Has all the rights as of CELLADMIN user Default password-welcome1 Aman Sharma-OTNYatra

29 Oracle Exadata Machine Storage Server- Storage Layout Cell Server System LUN s Cell Disks Aman Sharma-OTNYatra

30 Oracle Exadata Machine Storage Server- Storage Layout Grid Disk(s) Cell Disk Aman Sharma-OTNYatra

31 Oracle Exadata Machine Storage Server- Storage Layout Grid Disk(s) ASM Disk(s) Aman Sharma-OTNYatra

32 That s All For Exadata Today! Exadata is an awesome combination of software & hardware Exadata does nt mean that a DBA is not needed VM images of Exadata are NOT available Exadata is the future! Aman Sharma-OTNYatra

33 Exadata-Useful Books Aman Sharma-OTNYatra

34 Exadata-Useful MOS# s & URL s ase/high_availability/exadata Information Center: Oracle Exadata Database Machine ( ) Information Center: Installing and Configuring Oracle Exadata Database Machine ( ) Exadata Database Machine and Exadata Storage Server Supported Versions ( ) Oracle Exadata Best Practices ( ) Oracle Database Machine Monitoring Best Practices ( ) Aman Sharma-OTNYatra

35 Thank You Aman Sharma-OTNYatra