Inside Oracle Exalytics and Oracle TimesTen for Exalytics - Hotsos 2012

T : +44 (0) 8446 697 995 or (888) 631 1410 (USA) E : [email protected] W: www.rittmanmead.com

Mark Rittman, Technical Director, Rittman MeadHotsos Symposium 2012, Dallas

Inside Exalytics and Oracle TimesTen for Exalytics

mailto:[email protected]


Mark Rittman

•Mark Rittman, Co-Founder of Rittman Mead•Oracle ACE Director, specialising in Oracle BI&DW•14 Years Experience with Oracle Technology•Regular columnist for Oracle Magazine•Author of forthcoming Oracle Press book on OBIEE 11g•Writer for Rittman Mead Blog :

http://www.rittmanmead.com/blog•Email : [email protected]•Twitter : @markrittman

•First time at the Hotsos Symposium ;-)


http://www.rittmanmead.com/blog



About Rittman Mead

•Oracle BI and DW platinum partner•World leading specialist partner for technical excellence, solutions delivery and innovation in

Oracle BI•Approximately 50 consultants worldwide•All expert in Oracle BI and DW•Offices in US (Atlanta), Europe, Australia and India•Skills in broad range of supporting Oracle tools:

‣OBIEE‣OBIA‣ODIEE‣Essbase, Oracle OLAP‣GoldenGate‣Exadata ‣Endeca



Agenda

•Introduction, and the context for Exalytics•Oracle Exalytics BI Machine•Exalytics Under the Covers•TimesTen for Exalytics•Summary



What is Oracle Business Intelligence?

•Oracle BI provides a set of web-based tools for reporting and analyzing data•Based around dashboards, built around graphs, tables, pivots etc•Multiple server architecture that splits data access / presentation elements•Based on Siebel Analytics technology•Connects to multiple data sources

‣Oracle DB & Exadata‣SQL Server, DB/2, Teradata‣Essbase, Oracle OLAP, MSAS‣ADF View Objects etc

•Now re-engineered as part of FMW11g



Oracle BI within the Oracle BI/DW Technology Stack

•BI provides the query and presentation element for BI/DW•Catalog of reports, analyses, alerts, KPIs•Additional calculation and

data federation capabilities•Aggregate navigation•Security, scoping of data

ERP/Apps EssbaseDW

SAN / NAS

Oracle BI

Web Server



How Oracle Business Intelligence 11g Works

•Data sources are mapped into an internaldimensional model called the Oracle BI Repository

•Users request data through analyses, whichtranslate into logical SQL requests

•The Oracle BI Server converts these logicalSQL requests into one or more physicalSQL, MDX or other queries

•These are then processed by the underlyingdata sources, using their optimizations

•Data is then combined and returnedto users in the form of dashboards



In a BI/DW System, Where Does the Time and Heavy Lifting Go?

•Ideal is to return data to users with consistent sub-second response times•But large data volumes and unpredictable queries can make this tough•When analyzing query response times, most of the times goes in

‣The database returning the query results‣The storage tier returning data to the database‣The network connecting storage and the database

•Tuning, efficient queries and Exadata can help with this‣But queries can still sometimes take >2 mins or so‣And query times can be erratic

- Some are instant- Some take 2-3 minutes- Depends on load on the database

ERP/Apps DW

SAN / NAS

Oracle BI



BI System Performance Objectives

•Every query returns data immediately•No performance penalty for drilling-into and investigating the data•Response time is consistent•Response-time stays constant even when you scale up to 100’s of users



OBIEE Dashboard without Exalytics Optimizations

Demonstration



Potential Solutions to Query Performance Issues

•Buy an Exadata box (or several Exadata boxes...)•Add materialized views, more indexes, in-database OLAP to the DW•Move data into an OLAP server such as Essbase•But...

‣Can be expensive‣Adds to DBA complexity‣Requires new skills (Essbase etc)‣Scaling issues for OLAP servers



Another Solution - In-Memory Databases

•Move some, or all, of the data being queried into RAM•Sub-second response times•Consistent response times•A solution being applied elsewhere for similar problems

ERP/Apps DW

SAN / NAS

Oracle BI

In-Memory DB/Cache



Oracle Exalytics In-Memory Machine X2-4

•BI Appliance that combines hardware + BI software•Sun hardware, Four Intel Xeon E7-4800 series processors•1TB of RAM, made up of 64 16GB DDR3 ECC registered DIMMs•QDR (40Gb/second) InfiniBand connectivity to Exadata & Exalogic•10Gb and 1Gb Ethernet interfaces•Optimized version of Oracle BI EE•In-memory version of Oracle Essbase•3.6TB of disk, for internal use•Integrated Lights-Out Mgmt (ILOM)•Sold as an appliance/engineered system

‣Software only available in combination with hardware



Exalytics as the Exa-Machine for BI

•Runs the BI layer on a high-performance, multi-core, 1TB server•In-memory cache used to accelerate the BI part of the stack•If Exadata addresses 80% of the query performance,

Exalytics addresses the remaining 20%‣Consistent response times for queries‣In-memory caching of aggregates‣40 cores for high concurrency‣Re-engineered BI and OLAP software

that assumes 40 cores and 1TB RAM

ERP/Apps DW

Oracle BI

In-Memory DB/Cache



Enables High-Density Analysis of Big Data

•BI tier is rarely the bottleneck, but it can be if very dense visualizations are used‣Sparklines, grid of charts etc

•Exalytics’ 40 cores and 1TB RAM make higher density presentation viable‣Single query sent to the database‣Exalytics breaks data up to create microcharts

•Also helps support high numbers of concurrent users (100+)



What is Exalytics?

•Hardware Element‣Sun Fire X4470 M2 server‣1TB RAM, 40 Cores, 3.6TB HDD

•Software Element‣OBIEE 11.1.1.6 with Exalytics Enhancements‣Oracle Essbase 11.1.2 with Exalytics Enhancements‣Oracle TimesTen 11.2.2.2 for Exalytics‣Runs on 64-bit Oracle Linux

(Exalogic distribution)•OBIEE and Essbase are licensed as

Oracle BI Foundation•Exalytics features can only be used in

conjunction with Exalytics hardware



Exalytics Architecture

•Developer tools used for definingand maintaining aggregate definitions

•Client tools for OBIEE repository,TimesTen and Oracle Database

•Exalytics layer contains OBIEE,TimesTen and Essbase(not pictured)

•Database tier contains FMWdatabase repository, includingusage tracking and summary statistics

Developer Workstation

Oracle BI Administration Tool

Summary Advisor Wizard

nqcmd

TimesTen Client

SQL Developer

Oracle Database 11g Client

Oracle Business IntelligenceOracle TimesTen for Exalytics

WLS AdminServer

WLS ManagedServer

Oracle BISystem Comp.

BI Server

Aggregate Schema

Database for RCU Schemas

Enhanced Usage TrackingSummary Statistics



Exalytics Under the Covers - How Does it Work?

• Exalytics brings together different technologies, which are still standalone products in their own right

• To harmonise and optimise their use within Exalytics, it utilises the following techniques:‣ In-Memory Adaptive Data Mart‣ In-Memory Intelligent Result Cache‣ In-Memory Cubes

• Some of these are genuine "secret sauce"‣ New functionality and algorithms‣ You can only get them through licensing Exalytics

• Others are descriptions of DW/BI strategies, or existing product functionality, extended to take advantage of the capacity for processing in memory that Exalytics has



In-Memory Adaptive Data Mart

•Commonly-used aggregates are copied into Oracle TimesTen for Exalytics•Past query patterns are analyzed and suitable aggregates recommended•Oracle BI Server then uses these aggregates to make queries run faster•Aggregates change over time in

response to changes in query patterns•Tools are provided for managing

and populating these aggregates

TimesTen BI Server

Exa

lyti

cs

Aggregates

Data Warehouse

Detail-levelData



In-Memory Intelligent Results Cache

•OBIEE has an advanced result cache, which can support:‣Queries matching previous ones‣Queries matching a subset of the results of a cached query resultset ‣Queries aggregating the results of a cached query resultset

•Stored in cache files on the OBIEE server filesystem•With Exalytics, the 1TB of RAM typically means

that these files are held in memory•RAMdisk can also be created for

BI Server & Presentation Serverworking area files

TimesTen BI Server

Exa

lyti

cs

In-Memory Result Cache



In-Memory Essbase Cubes

•Essbase is being enhanced to provide better in-memory capabilities•Some features will be common to all Essbase releases, some will require Exalytics

‣Smart Storage Manager stores frequently access blocks in-memory‣In-Memory Cache optimizes block access‣Lock Manager improves parallelism



So What is Oracle TimesTen (for Exalytics?)

•TimesTen dates back to 1998, acquired by Oracle in 2005‣It is an In-Memory Database‣The whole of the database is loaded into memory‣It is persisted to disk, for full recovery capabilities

•Originally designed for exceptionally fast and highly concurrent read/write of single rows of data (airline booking, trading desks, etc)

•Can be deployed in two ways: ‣Standalone database‣In conjunction with Oracle, as part of In Memory Database Cache

•Previous versions of TimesTen were usable with OBIEE, but...‣Because of its focus on fast OLTP, was slow for reporting‣Limited analytical capabilities



Oracle TimesTen for Exalytics

•New version of TimesTen specifically for Exalytics (and only available with Exalytics)•Support for analytic functions

‣Perform all the processing at source‣Combine with being in-memory = should be very fast

•Column compression‣Whitepaper cites 5x‣Given the hardware capacity, we could seriously contemplate loading the whole Data

Warehouse into memory‣Opens up lots of interesting design potential

•We can load aggregates into TimesTen, leave base data at source, and use OBIEE’s Vertical Federation capability to seamlessly report across both‣All hidden from the end-user, all they will know is that their reports run fast!



TimesTen and OBIEE Architecture

•Oracle BI Server communicates with TimesTen through TimesTen Client•Summary Advisor, and nqcmd use Oracle BI Server to access TimesTen•Typical single TimesTen database per Exalyics machine

‣Max TimesTen database size around 300MB- Due to need to set aside equal

Temp size for the Perm size selected•Clustered Exalytics boxes can be daisy-chained

together using InfinBand connections‣For HA scenarios, does not increase

available RAM‣Summary advisor scripts write to both TimesTen

databases, replicating aggregates‣TimesTen databases can be “wired together”

for failover/HA purposes

TimesTenMemory-ResidentDatabase

CheckpointFiles

LogFiles

ODBC

Oracle BIServer

nqcmdSummaryAdvisor



TimesTen Extensions for Exalytics

•Notable new functionality in this version includes: ‣Columnar Compression‣Analytic functions: AVG, SUM, COUNT, MAX, MIN, DENSE_RANK, RANK,

ROW_NUMBER, FIRST_VALUE and LAST_VALUE‣Analytic clauses: OVER PARTITION BY and OVER ORDER BY‣Grouping clauses: GROUP BY CUBE, GROUP BY ROLLUP, GROUP BY GROUPING

SETS‣Grouping functions: GROUP, GROUPING_ID, GROUP_ID‣WITH clause‣Aggregate expressions over DISTINCT expressions



TimesTen for Exalytics Columnar Compression

•The version of TimesTen for Exalytics features “In-memory columnar compression”•Compression is specified against individual columns, or groups of columns•Some will compress better than others

‣A compression group is where the same compression dictionary is applied to values in the columns within it

‣Examples of use would be surname & maiden name, home_city & city_of_birth•Compressed columns take slightly longer to load, but should:

‣be faster to query than uncompressed columns‣take up less disk space‣Compression typically reduces the 3x overhead of usual TT storage (compared to

source data in a file) back to the original dataset size



Enabling Columnar Compression in the Administration Tool

•When initially created, the TimesTen database used by Exalytics is set up withoutcolumnar compression enabled

•To enable, check the Compress Columns checkbox in the Database Features dialog‣Also, disable WITH_CLAUSE_SUPPORTED‣TimesTen can use them in SELECTS, but not

during data load (disable during loads only?)



Summary Advisor within Oracle BI Administration Tool

•Utility within Oracle BI Administrator tool that recommends aggregates•Bases recommendations on usage tracking and summary statistics data•Captured based on past activity•Runs an iterative algorithm that searches,

each iteration, for the best aggregate

ProposedAggregate Fact TableRow Count

ExisitngBase Fact TableRow Count

20 rows

100000 rows

X PreviousQuery Time

30 secs =PredictedNew Query Time

0.06 secs



Underlying Enhanced Usage Tracking Data

•Historically, usage tracking has been tracked using S_NQ_ACCT‣Holds basic usage tracking statistics + logical SQL query

•Now supplemented by S_NQ_DB_ACCT ‣Extra usage tracking information, includes physical SQL

•Exalytics Summary Advisor uses S_NQ_SUMMARY_ADVISOR‣Contains summary statistics, execution time etc‣Gathered at same time as usage tracking when

Exalytics is enabed‣Contents can be derived from usage tracking if needed



Required Configuration Steps for Exalytics/Summary Advisor

1. Configure TimesTen DSN for in-memory aggregates2. Configure opmn.xml in middleware home for TIMESTEN_DLL3. Create TimesTen database, user account and permissions4. Create sample table in TT database using SQL*Developer5. Import or create the TT table in RPD6. Add usage tracking and summary statistics tables to RPD7. Enable usage tracking via EM/MBean8. Restart system

Assumes system has been enabled for Exalytics by Oracle ACS or Partner



The Oracle Exalytics Summary Advisor

Demonstration



Creating In-Memory Aggs Step 1 : Select Facts and Time Scope

•Select Tools > Utilities > Summary Advisor•Select facts from the BMM layer to consider for the exercise

‣Can also generate stats from usage tracking data if none exists (upgrade etc)‣And can load parameters from a file

•Select start and end date for wizard to consider (optional)



Creating In-Memory Aggregates Step 2 : Set Min Query Time, Target

•Select minimum elapsed time for queries, to consider for exercise•Select physical database details for TT database



Creating In-Memory Aggregates Step 3 : Set Script Target Location

•Summary Advisor will generate a script that has to be run through nqcmd.exe‣Same type of script as generated by Aggregate Persistence Wizard

•Script can be re-run to refresh aggregates periodically‣Drops and recreates aggregates, no incremental refresh



Creating In-Memory Aggregates Step 4 : Define Stopping Criteria

•Select maximum run-time for summary advisor (0=unlimited time)‣Useful when lots of summary statistics data to process

•Set limit for how little each additional aggregate improves performance‣Stops lots of little aggregates that barely improve performance being recommended‣Ideally, set to around 10% for good balance

between good recommendations andgood dashboard performance



Creating In-Memory Aggregates Step 5 : Run + Filter Recommends

•Aggregate recommendations can then be generated•Filter page lets you select which ones to implement

‣Suggested approach is to add one aggregate at a time, test and implement‣For smaller, more tested RPDs you can select all if required



Creating In-Memory Aggregates Step 6 : Generate Aggregates

•Wizard then creates the script, which can be run through the nqcmd utility‣Command-line access to the BI Server

•Run command either at the developer workstation, or on the Exalytics server•Re-run at any time to refresh aggregate tables with new data

cd [obiee_client_home]\oraclebi\orahome\bifoundation\server\bin\nqcmd.exe -d exalytics -u biadmin -p welcome1-s c:\summary_advisor_scripts\agg_wiz.sql



What Does the Summary Advisor Create?

•Aggregate tables in the TimesTen database‣One per aggregate fact table‣One per shared dimension

•Physical tables in the Oracle BI Repository physical layer•Logical Table Sources in the BMM layer

‣All mapped in and active



Oracle BI Server then Redirects Queries to Aggregates

•When users then query the dashboard, queries will get redirected to the TimesTen tables

•Aggregate navigation is additive, so single aggregates should satisfy other queries

TimesTen BI Server

Exa

lyti

cs

Aggregates

Data Warehouse

Detail-levelData

Sending query to database named TT_AGGR_STORE, connection pool named TT_AGGR_STORE, logical request hash 9b1a12f5, physical request hash 2f1461f5: [[select sum(T44087.Billed_Qua0000A5C2) as c1, sum(T44087.Revenue0000A5BC) as c2from ag_2123023723 T44087



Summary Advisor Usage Recommendations & Limitations

•Start by generating and testing single aggregates each time‣If one aggregate creation fails, whole process fails; tricky to “un-pick” process‣Focus on a few facts, recover any errors, then move to next facts

•Constraint time window to a representative range•Be aware of how best to use the repository and source data

‣Run “estimate levels” prior to Summary Advisor, helps to ensure unique level keys‣Do not run against value-based hierarchies, or skip-level/ragged (not supported)‣Cleanse data before running Summary Advisor - ensure unique level keys, no

NULLs in dimension key references‣Implement indices on the source systems



Alternative Use Case : Manually Load “Hot” Data into TimesTen

•Summary Advisor only loads recommended aggregates into TimesTen‣Usually a good approach, as based on historic usage and expected gain

•It is possible to manually load source data into TimesTen‣Aggregates using Aggregate Persistence Wizard‣ETL using ODI‣Replication using Golden Gate

•Aggregates would get automatically mapped in RPD•ETL’d data would need manual mapping

‣Replacement LTSs‣Fragmentation‣Additional LTSs

•Remember TT RAM restriction:maximum of around 300GB



Troubleshooting and Diagnostics

•Enable detailed logging for summary advisor scripts‣Session variable in RPD: LOGLEVEL >=4‣Prefix aggregate statements-set variable LOGLEVEL=4 : delete aggregates-set variable LOGLEVEL=4 : create aggregates

•Logs in nqquery.log, Errors in nqserver.log•Enable detailed logging for the Admin tool

‣ [instances]\instance1\config\OracleBIServerComponent\coreapplication_obis1\logconfig.xml

‣ <Level> <IncidentError>1</IncidentError> <Error>1</Error> <Warning>1</Warning> <Trace>32</Trace></Level>



How Does it Perform?

•Have performed some software-only testing, but Exalytics box not yet available•Performed some standalone testing of TimesTen, and also compared TimesTen

queries to standard queries•Difficult to judge without

‣Running on an Exalytics box - BI Server has optimizations for this hardware‣Representative data volumes

•Keep an eye on our blog for findings once the box is delivered‣http://www.rittmanmead.com/blog


http://www.rittmanmead.com/blog


OBIEE Dashboard following Exalytics Optimizations

Demonstration



In-Memory Aggregate Caching Benefits & Limitations

•For individual dashboards, analyses etc, caching works well•For general aggregate re-usability, depends on rest of model, query types etc

‣Use in conjunction with results caching; similar benefits and limitations•Caching (of aggregates) makes TimesTen not suitable for real-time (OLTP) sources•Needs to be used in conjunction with database and storage tuning

‣Ideal link is with Exadata (uses InfinBand)



Summary

•Well it certainly looks interesting...!•Exalytics’ 40 core server with 1TB of RAM provides a very fast hardware platform•Addresses the “mid-tier” performance issue for BI systems•Infiniband connnection makes integration with Exadata particularly effectivee•TimesTen for Exalytics provides the in-memory database cache•Tools provided as part of Exalytics make it possible to intelligently populate the cache•Benefits for Essbase users in-terms of specific optimizations for Essbase•Looking forward now to getting our hands on the hardware

‣Contact us for a Proof of Concept exercise, using our “Exa-lab” in Brighton, UK



More Information

•Thank you for attending this presentation•More information can be found at http://www.rittmanmead.com•Contact us at [email protected] or [email protected]•Look out for our book, “Oracle Business Intelligence Developers Guide” due Q3 2012•Follow-us on Twitter (@rittmanmead) or Facebook (facebook.com/rittmanmead)


http://www.rittmanmead.com/




Mark Rittman, Technical Director, Rittman MeadHotsos Symposium 2012, Dallas

Inside Exalytics and Oracle TimesTen for Exalytics