Integrated Data Management




Managing Large Data Sets for Smart Meters

Jacques Roy, IBM
·Click to add text
jacquesr@us.ibm.com

                                            © 2011 IBM Corporation
Integrated Data Management



    Overview

    • How much data do smart meters generate?
    • Introducing Informix TimeSeries benefits
    • Some technical details
    • Proof points
    • Solution partners
    • Demo




2                                                © 2011 IBM Corporation
Integrated Data Management



           Utility-Scale Smart Meter Deployments, Plans &
                              Proposals*
                                                        September 2010




                                                                                                 Deployment for
                                                                                                 >50% of end-users

                                                                                                 Deployment for
                                                                                                 <50% of end-users


    *This map represents smart meter deployments,
    planned deployments, and proposals by investor-
    owned utilities and large public power utilities.
                                                                         © 2010 The Institute for Electric Efficiency
                                                                            http://www.edisonfoundation.net/IEE/

3                                                                                                   © 2011 IBM Corporation
Integrated Data Management



Example of Changing Storage Requirements
    Changing Workloads For 10 Million Smart Meters:
    Now – Each meter read once per month
    Very soon – Each meter read once every 15 minutes (2920X)
    Regulations – Need to keep data on line for 3 years (PUC) and, perhaps, save for 7 years

                           Data for a Utility In California         350.4B



# of Records
Per Year for
 10M meters


                                                    3.65B
                       120M

                                                                                  Frequency
                   Monthly Meter                Daily Meter     15 Minute Meter   of reads
                      Reads                       Reads             Reads
4                                                                                  © 2011 IBM Corporation
Integrated Data Management



     Keeping up with Smart Meter Data

    Large amounts of data causes problems in 2 areas:

    A) Storage management
       • Will get expensive and cumbersome to maintain

    • Query performance
       • Compliance Reports must be completed before the end of each day
       • Customer portal queries must be handled in a timely manner
       • Customer billing




5                                                                    © 2011 IBM Corporation
Integrated Data Management



       Introducing IBM Informix Relational Database
    • Why IBM Informix?
      • Low cost/Low administration
        • Manage thousands of servers with one database administrator
        • Many installations have no DBA’s


      • High performance
        • Insert 100’s of thousands of records per second
        • Analytic functions not available in other database products


      • High Availability
        • Scale up, scale out, and disaster recovery


      • Native time series data support
        • Load and analyze time series data


 “The idea was to run the project in three cycles, and use a different type of analysis in each cycle, to see if we
could draw any conclusions in terms of how to promote change in the way people view their energy
consumption. With help from the IBM Hursley team, we quickly found that Informix TimeSeries could deliver
spectacular results.” Clive Eisen, Chief Technology Officer at Hildebrand.
6                                                                                                   © 2011 IBM Corporation
Integrated Data Management



    Key Strengths of Informix TimeSeries
    •   Performance
        • Extremely fast data access
           • Data clustered and sorted by time on disk to reduce I/O
        • Handles operations hard or impossible to do in standard SQL
        • Continuous Real-Time and Batch Data Loaders

    •   Space Savings
        • Typically saves 50% space over standard relational layout

    •   Toolkit approach
        • Allows users to develop their own algorithms to run in the database
        • Algorithms running in the database leverage the buffer pool for speed

    •   Easier
        • Conceptually closer to how users think of time series


7                                                                                 © 2011 IBM Corporation
Integrated Data Management


Typical Relational Schema for Smart Meters Data
                            Index                 Smart_Meters
                                                     Table
                    meter_id        Time         KWH        Voltage          ColN
                        1         1-1-11 12:00    Value 1   Value 2   ……..   Value N
      Table Grows




                        2         1-1-11 12:00    Value 1   Value 2   ……..   Value N

                        3         1-1-11 12:00    Value 1   Value 2   ……..   Value N

                       …               …             …        …       ……..     …

                        1         1-1-11 12:15    Value 1   Value 2   ……..   Value N

                        2         1-1-11 12:15    Value 1   Value 2   ……..   Value N

                        3         1-1-11 12:15    Value 1   Value 2   ……..   Value N

                       …               …             …        …       ……..     …


                    • Each row contains exactly one record = billions of rows
                    • Additional indexes are required for efficient lookups
                    • Data is appended to the end of the table as it arrives
                    • Meter Id’s stored in every record
                    • No concept of a missing row
8                                                                                      © 2011 IBM Corporation
Integrated Data Management



    Same Table using an Informix TimeSeries Schema
                                           Smart_Meters
                                              Table
    meter_id                                            Series
         1         [(1-1-11 12:00, value 1, value 2, …, value N), (1-1-11 12:15, value 1, value 2, …, value N), …]

         2         [(1-1-11 12:00, value 1, value 2, …, value N), (1-1-11 12:15, value 1, value 2, …, value N), …]

         3         [(1-1-11 12:00, value 1, value 2, …, value N), (1-1-11 12:15, value 1, value 2, …, value N), …]

         4         [(1-1-11 12:00, value 1, value 2, …, value N), (1-1-11 12:15, value 1, value 2, …, value N), …]

         …                                                       …


                                            Table grows

    • Each row contains a growing set of records = one row per meter
    • Data append to a row rather than to the end of the table
    • Meter Ids not stored in individual records
    • Data is clustered by meter id and sorted by time on disk
    • Missing values take no disk space, missing interval reads take 2 bytes
9                                                                                                     © 2011 IBM Corporation
Integrated Data Management



     Informix TimeSeries: Key Concepts
      • DBSpace
       • A logical unit of storage used by the database server
       • Made up of one or more physical storage units called chunks

      • Containers
       • Specialized storage for TimeSeries in dbspaces

      • TimeSeries data element: row type
       • Flexibility to define as many parts as needed

      • TimeSeries types: regular, irregular
       • Covers regular intervals and sparse data distribution

      • Calendar
       • Defines business patterns

      • Relational view: VTI and processing return type

10                                                                     © 2011 IBM Corporation
Integrated Data Management



     Informix TimeSeries: Space savings

      • Example of simple meter record:
       {loc_id, timestamp, register_1, register_2, register_3}
        8 bytes 12 bytes 4 bytes       4 bytes     4bytes

      • TimeSeries savings: no duplication of loc_id, timestamp
       • Record size: 12 bytes instead of 32 bytes

      • Impact: 10M meters, 3 years, 15-minute interval
       • Savings: ~20TB
         20 bytes * 10M meters * 96 intervals/day * 3 years * 365 days/year

      • Index on meter records:
       • Relational: 1 trillion entries on loc_id, timestamp
       • TimeSeries: 10M entries on loc_id



11                                                                      © 2011 IBM Corporation
Integrated Data Management



     Informix TimeSeries: I/O advantages

      • Less data to read, less index entries to navigate


      • Meter data grouped on pages
       • Reading 1 day of data → One I/O (+ index I/O)
       • Relational: no grouping guarantees, could be 96 I/Os (+ index I/O)




12                                                                       © 2011 IBM Corporation
Integrated Data Management



     Informix TimeSeries: Processing advantages

      • TimeSeries data is accessed in time order
       • Relational model has no order guarantees – Sorting required

      • Library of SQL functions to process TimeSeries
       • 100+ functions
       • Ex: Aggregate data from 15-min interval to daily interval
             Calculate a moving average

      • Ability to write custom functions
       • Write business-specific processing
       • Streamline the processing instead of generic functions
         • Can greatly reduce code length → Significant performance
           improvements




13                                                                     © 2011 IBM Corporation
Integrated Data Management


     Informix TimeSeries vs Relational Database Systems
     Comparison of 1M Meter POC at Large US Energy Provider

                                      Informix              Competitor's Relational
1M Meter @ 15min POC                                                                    Improvement
                                      TimeSeries            Database System
Load Time                             18 Minutes            7 Hours                     23x faster
Report Generate Time                  Seconds to 11 min     2-7 HOURS                   38x faster
Storage Space                         350GB                 1.3 TB                      <1/3 storage


                   IBM Informix TimeSeries
                   Relational Database System                                             Based on actual
                                                                                        benchmark test run
                                                                                        for a large electrical
                                                                                           utility company
 Processing                                               Disk
    Time                                                  Storage
  (Hours)                                                 Space




            Data Loading      Reports                                 Relational   IBM Informix
                                                                      Database     TimeSeries


14                                                                                         © 2011 IBM Corporation
Integrated Data Management


         Informix TimeSeries vs Relational Database Systems
         Comparison of Published Benchmarks for Meter Data Management
                                                                           Daily           Total      Total                DB            App                 DB       App
                                                        Meters
                                                                           Reads           Cores      RAM                  cores         cores               RAM      RAM
      Informix TimeSeries                                                                                                                                             (shared
                                                        100M               4.9B            16         500                  16            (shared)            500
                                                                                                                                                                      )

      The Competition *                                 5.5M               1.06B           456        3668                 96            360                 768      2900


                         Daily Readings (meters * registers * intervals)                                                    Database Resources (CPU cores)




Informix TimeSeries                                                                4,900,000,000   Informix TimeSeries     16




     The Competition            1,061,500,000                                                         The Competition                                                  96




                       5 times the performance                                                                           < 1/5 the resources
      … with significantly simpler management using a single node system
     * Based on published Oracle benchmark
       http://www.oracle.com/us/industries/utilities/performance-benchmark-exadata-wp-161572.pdf
15                                                                                                                                                            © 2011 IBM Corporation
Integrated Data Management

      Informix TimeSeries – Success with leading MDM providers
http://smart-grid...                                    http://www.metering.com/node/20062




                                                       MDM offers scalability to 100 million smart meters




                 . “We feel that the Informix          “Performance testing results of
                 TimeSeries technology lends           AMT-SYBEX’s Affinity Meterflow
                 itself extremely well to the          meter data management (MDM)
                 performance characteristics, data     application using IBM Informix
                 types and high-volume                 TimeSeries software has
                 processing required for the next      demonstrated the capability to
                 generation of smart metering and      offer linear scalability up to 100
                 smart grid applications.”             million meters to load and
                 - David Hubbard, CTO and              process meter data at 30-minute
                 co-founder of Ecologic Analytics      intervals in less than 8 hours.”


 16                                                                                          © 2011 IBM Corporation
Integrated Data Management



     Client Success: Hildebrand

Hildebrand is a technology consultant company         on the Digital Environment Home Energy
Management System (DEHEMS) project. The Hildebrand team was asked by the UK government to find
a way to scale up its energy monitoring solution and enable it to monitor three million homes.


                         What’s Smart?
                         • Energy management thru real time monitoring
                         • Ability to monitor scales to over 3 million homes
                         • Reduced energy

                         Business Benefits
                         • Helping people make better decisions about energy efficiency in
                           the home.
                         • Collect, store and analyse up to • 50,000 data points per second
                         • Delivers high performance on low-cost hardware by leveraging
                           Informix time series data management technologies.




17                                                                               © 2011 IBM Corporation
Integrated Data Management



      Hildebrand: 3 Million Meters
 • Test involved 3,000,000 Homes                            • Hardware/Software Used
     • Data generated every 6 seconds!                        • Intel with 8 cores running:
                                                                • 64 bit SUSE Linux v10
 • Up to 26 values recorded                                     • 16 GB of memory
     • Meter ID                                               • Informix workgroup edition
     • Timestamp                                              • Hildebrand software
     • 3 Electricity phases
     • 1 Gas reading
     • 20 Individual electrical sockets in the house


 • Data collected every 6 seconds
     • Aggregated to per-minute readings
     • Minute readings bulk-loaded into Informix every 10
       minutes
     • Average load was about 50,000 inserts per second

18                                                                                  © 2011 IBM Corporation
Integrated Data Management



     Consumer Education




19                                        © 2011 IBM Corporation
Integrated Data Management



     AMT/SYBEX
     Proving the concept for smart metering data management
     • The Need:
       • Extend AMT/Sybex’s Data Transfer Solution to:                   “We owe a great deal to
         • Load, validate, store, and provide smart meter interval and   IBM, both for the Informix
           event data to external system                                 technology itself, and for the
                                                                         fantastic support from all
     • The Challenge:                                                    levels of the organisation.”
       • Process the enormous volume of data in a timely                      — Gordon Brown, DTS Product
         manner                                                                        Owner, AMT-SYBEX
       • Not to require a huge investment in new hardware
                                                                         Solution components:
     • The Solution:
                                                                          IBM® Informix® TimeSeries™
       • Combined effort with IBM Research and IBM Informix
       • Informix TimeSeries provides the core capabilities to            IBM Research
         store and process the meter and event data:
         •   VEE
         •   Real-time energy monitoring
         •   Analytics for developing new tariff rates
         •   Help to smooth peaks in demand




20                                                                                         © 2011 IBM Corporation
Integrated Data Management



     AMT/Sybex Tests and Performance Measurements
     The main tests for AMT-SYBEX were to prove key business functions at high
      volume:
         • Can high volumes of data be loaded into Smart DTS?
         • Can data be analyzed and processed in Smart DTS in a timely manner?

     To facilitate these requirements, the following tests were carried out:
         • These results are for 10 million meters storing data every ½ hour data for one day.

      Module                              Time                           Readings/intervals per
                                                                         second
      Technical Validation and            13 minutes                     >600,000
      Transformation
      High Speed TimeSeries               50 minutes                     >150,000
      database load (with full
      logging)
      Validation and Estimation           33 minutes                     >240,000



         Full processing end to end for 10 million meter points with half-hourly interval
         data on a single mid-range P-series 8 CPU server is just over 1 ½ hours

21                                                                                           © 2011 IBM Corporation

Ugif 12 2011-smart meters-11102011

  • 1.
    Integrated Data Management ManagingLarge Data Sets for Smart Meters Jacques Roy, IBM ·Click to add text jacquesr@us.ibm.com © 2011 IBM Corporation
  • 2.
    Integrated Data Management Overview • How much data do smart meters generate? • Introducing Informix TimeSeries benefits • Some technical details • Proof points • Solution partners • Demo 2 © 2011 IBM Corporation
  • 3.
    Integrated Data Management Utility-Scale Smart Meter Deployments, Plans & Proposals* September 2010 Deployment for >50% of end-users Deployment for <50% of end-users *This map represents smart meter deployments, planned deployments, and proposals by investor- owned utilities and large public power utilities. © 2010 The Institute for Electric Efficiency http://www.edisonfoundation.net/IEE/ 3 © 2011 IBM Corporation
  • 4.
    Integrated Data Management Exampleof Changing Storage Requirements Changing Workloads For 10 Million Smart Meters: Now – Each meter read once per month Very soon – Each meter read once every 15 minutes (2920X) Regulations – Need to keep data on line for 3 years (PUC) and, perhaps, save for 7 years Data for a Utility In California 350.4B # of Records Per Year for 10M meters 3.65B 120M Frequency Monthly Meter Daily Meter 15 Minute Meter of reads Reads Reads Reads 4 © 2011 IBM Corporation
  • 5.
    Integrated Data Management Keeping up with Smart Meter Data Large amounts of data causes problems in 2 areas: A) Storage management • Will get expensive and cumbersome to maintain • Query performance • Compliance Reports must be completed before the end of each day • Customer portal queries must be handled in a timely manner • Customer billing 5 © 2011 IBM Corporation
  • 6.
    Integrated Data Management Introducing IBM Informix Relational Database • Why IBM Informix? • Low cost/Low administration • Manage thousands of servers with one database administrator • Many installations have no DBA’s • High performance • Insert 100’s of thousands of records per second • Analytic functions not available in other database products • High Availability • Scale up, scale out, and disaster recovery • Native time series data support • Load and analyze time series data “The idea was to run the project in three cycles, and use a different type of analysis in each cycle, to see if we could draw any conclusions in terms of how to promote change in the way people view their energy consumption. With help from the IBM Hursley team, we quickly found that Informix TimeSeries could deliver spectacular results.” Clive Eisen, Chief Technology Officer at Hildebrand. 6 © 2011 IBM Corporation
  • 7.
    Integrated Data Management Key Strengths of Informix TimeSeries • Performance • Extremely fast data access • Data clustered and sorted by time on disk to reduce I/O • Handles operations hard or impossible to do in standard SQL • Continuous Real-Time and Batch Data Loaders • Space Savings • Typically saves 50% space over standard relational layout • Toolkit approach • Allows users to develop their own algorithms to run in the database • Algorithms running in the database leverage the buffer pool for speed • Easier • Conceptually closer to how users think of time series 7 © 2011 IBM Corporation
  • 8.
    Integrated Data Management TypicalRelational Schema for Smart Meters Data Index Smart_Meters Table meter_id Time KWH Voltage ColN 1 1-1-11 12:00 Value 1 Value 2 …….. Value N Table Grows 2 1-1-11 12:00 Value 1 Value 2 …….. Value N 3 1-1-11 12:00 Value 1 Value 2 …….. Value N … … … … …….. … 1 1-1-11 12:15 Value 1 Value 2 …….. Value N 2 1-1-11 12:15 Value 1 Value 2 …….. Value N 3 1-1-11 12:15 Value 1 Value 2 …….. Value N … … … … …….. … • Each row contains exactly one record = billions of rows • Additional indexes are required for efficient lookups • Data is appended to the end of the table as it arrives • Meter Id’s stored in every record • No concept of a missing row 8 © 2011 IBM Corporation
  • 9.
    Integrated Data Management Same Table using an Informix TimeSeries Schema Smart_Meters Table meter_id Series 1 [(1-1-11 12:00, value 1, value 2, …, value N), (1-1-11 12:15, value 1, value 2, …, value N), …] 2 [(1-1-11 12:00, value 1, value 2, …, value N), (1-1-11 12:15, value 1, value 2, …, value N), …] 3 [(1-1-11 12:00, value 1, value 2, …, value N), (1-1-11 12:15, value 1, value 2, …, value N), …] 4 [(1-1-11 12:00, value 1, value 2, …, value N), (1-1-11 12:15, value 1, value 2, …, value N), …] … … Table grows • Each row contains a growing set of records = one row per meter • Data append to a row rather than to the end of the table • Meter Ids not stored in individual records • Data is clustered by meter id and sorted by time on disk • Missing values take no disk space, missing interval reads take 2 bytes 9 © 2011 IBM Corporation
  • 10.
    Integrated Data Management Informix TimeSeries: Key Concepts • DBSpace • A logical unit of storage used by the database server • Made up of one or more physical storage units called chunks • Containers • Specialized storage for TimeSeries in dbspaces • TimeSeries data element: row type • Flexibility to define as many parts as needed • TimeSeries types: regular, irregular • Covers regular intervals and sparse data distribution • Calendar • Defines business patterns • Relational view: VTI and processing return type 10 © 2011 IBM Corporation
  • 11.
    Integrated Data Management Informix TimeSeries: Space savings • Example of simple meter record: {loc_id, timestamp, register_1, register_2, register_3} 8 bytes 12 bytes 4 bytes 4 bytes 4bytes • TimeSeries savings: no duplication of loc_id, timestamp • Record size: 12 bytes instead of 32 bytes • Impact: 10M meters, 3 years, 15-minute interval • Savings: ~20TB 20 bytes * 10M meters * 96 intervals/day * 3 years * 365 days/year • Index on meter records: • Relational: 1 trillion entries on loc_id, timestamp • TimeSeries: 10M entries on loc_id 11 © 2011 IBM Corporation
  • 12.
    Integrated Data Management Informix TimeSeries: I/O advantages • Less data to read, less index entries to navigate • Meter data grouped on pages • Reading 1 day of data → One I/O (+ index I/O) • Relational: no grouping guarantees, could be 96 I/Os (+ index I/O) 12 © 2011 IBM Corporation
  • 13.
    Integrated Data Management Informix TimeSeries: Processing advantages • TimeSeries data is accessed in time order • Relational model has no order guarantees – Sorting required • Library of SQL functions to process TimeSeries • 100+ functions • Ex: Aggregate data from 15-min interval to daily interval Calculate a moving average • Ability to write custom functions • Write business-specific processing • Streamline the processing instead of generic functions • Can greatly reduce code length → Significant performance improvements 13 © 2011 IBM Corporation
  • 14.
    Integrated Data Management Informix TimeSeries vs Relational Database Systems Comparison of 1M Meter POC at Large US Energy Provider Informix Competitor's Relational 1M Meter @ 15min POC Improvement TimeSeries Database System Load Time 18 Minutes 7 Hours 23x faster Report Generate Time Seconds to 11 min 2-7 HOURS 38x faster Storage Space 350GB 1.3 TB <1/3 storage IBM Informix TimeSeries Relational Database System Based on actual benchmark test run for a large electrical utility company Processing Disk Time Storage (Hours) Space Data Loading Reports Relational IBM Informix Database TimeSeries 14 © 2011 IBM Corporation
  • 15.
    Integrated Data Management Informix TimeSeries vs Relational Database Systems Comparison of Published Benchmarks for Meter Data Management Daily Total Total DB App DB App Meters Reads Cores RAM cores cores RAM RAM Informix TimeSeries (shared 100M 4.9B 16 500 16 (shared) 500 ) The Competition * 5.5M 1.06B 456 3668 96 360 768 2900 Daily Readings (meters * registers * intervals) Database Resources (CPU cores) Informix TimeSeries 4,900,000,000 Informix TimeSeries 16 The Competition 1,061,500,000 The Competition 96 5 times the performance < 1/5 the resources … with significantly simpler management using a single node system * Based on published Oracle benchmark http://www.oracle.com/us/industries/utilities/performance-benchmark-exadata-wp-161572.pdf 15 © 2011 IBM Corporation
  • 16.
    Integrated Data Management Informix TimeSeries – Success with leading MDM providers http://smart-grid... http://www.metering.com/node/20062 MDM offers scalability to 100 million smart meters . “We feel that the Informix “Performance testing results of TimeSeries technology lends AMT-SYBEX’s Affinity Meterflow itself extremely well to the meter data management (MDM) performance characteristics, data application using IBM Informix types and high-volume TimeSeries software has processing required for the next demonstrated the capability to generation of smart metering and offer linear scalability up to 100 smart grid applications.” million meters to load and - David Hubbard, CTO and process meter data at 30-minute co-founder of Ecologic Analytics intervals in less than 8 hours.” 16 © 2011 IBM Corporation
  • 17.
    Integrated Data Management Client Success: Hildebrand Hildebrand is a technology consultant company on the Digital Environment Home Energy Management System (DEHEMS) project. The Hildebrand team was asked by the UK government to find a way to scale up its energy monitoring solution and enable it to monitor three million homes. What’s Smart? • Energy management thru real time monitoring • Ability to monitor scales to over 3 million homes • Reduced energy Business Benefits • Helping people make better decisions about energy efficiency in the home. • Collect, store and analyse up to • 50,000 data points per second • Delivers high performance on low-cost hardware by leveraging Informix time series data management technologies. 17 © 2011 IBM Corporation
  • 18.
    Integrated Data Management Hildebrand: 3 Million Meters • Test involved 3,000,000 Homes • Hardware/Software Used • Data generated every 6 seconds! • Intel with 8 cores running: • 64 bit SUSE Linux v10 • Up to 26 values recorded • 16 GB of memory • Meter ID • Informix workgroup edition • Timestamp • Hildebrand software • 3 Electricity phases • 1 Gas reading • 20 Individual electrical sockets in the house • Data collected every 6 seconds • Aggregated to per-minute readings • Minute readings bulk-loaded into Informix every 10 minutes • Average load was about 50,000 inserts per second 18 © 2011 IBM Corporation
  • 19.
    Integrated Data Management Consumer Education 19 © 2011 IBM Corporation
  • 20.
    Integrated Data Management AMT/SYBEX Proving the concept for smart metering data management • The Need: • Extend AMT/Sybex’s Data Transfer Solution to: “We owe a great deal to • Load, validate, store, and provide smart meter interval and IBM, both for the Informix event data to external system technology itself, and for the fantastic support from all • The Challenge: levels of the organisation.” • Process the enormous volume of data in a timely — Gordon Brown, DTS Product manner Owner, AMT-SYBEX • Not to require a huge investment in new hardware Solution components: • The Solution:  IBM® Informix® TimeSeries™ • Combined effort with IBM Research and IBM Informix • Informix TimeSeries provides the core capabilities to  IBM Research store and process the meter and event data: • VEE • Real-time energy monitoring • Analytics for developing new tariff rates • Help to smooth peaks in demand 20 © 2011 IBM Corporation
  • 21.
    Integrated Data Management AMT/Sybex Tests and Performance Measurements The main tests for AMT-SYBEX were to prove key business functions at high volume: • Can high volumes of data be loaded into Smart DTS? • Can data be analyzed and processed in Smart DTS in a timely manner? To facilitate these requirements, the following tests were carried out: • These results are for 10 million meters storing data every ½ hour data for one day. Module Time Readings/intervals per second Technical Validation and 13 minutes >600,000 Transformation High Speed TimeSeries 50 minutes >150,000 database load (with full logging) Validation and Estimation 33 minutes >240,000 Full processing end to end for 10 million meter points with half-hourly interval data on a single mid-range P-series 8 CPU server is just over 1 ½ hours 21 © 2011 IBM Corporation