Building%20BIG%20Data%20Servers%20on%20the%20Web

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Building BIG Data Servers on the Web
Talk at Flash Mob Supercomputer 3 April 2004

• Jim Gray
• Microsoft Research
• Gray_at_Microsoft.com
• http//research.microsoft.com/Gray

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NumbersTeraBytes and Gigabytes are BIG!

• Mega a house in san francisco
• Giga a very rich person
• Tera The Bush national debt
• Peta more than all the money in the world
• A Gigabyte the Human Genome
• A Terabyte 150 mile long shelf of books.

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How much information is there?
Yotta Zetta Exa Peta Tera Giga Mega Kilo

• Soon everything can be recorded and indexed
• Most bytes will never be seen by humans.
• Data summarization, trend detection anomaly
  detection are key technologies
• See Mike Lesk How much information is there
  http//www.lesk.com/mlesk/ksg97/ksg.html
• See Lyman Varian
• How much information
• http//www.sims.berkeley.edu/research/projects/how
  -much-info/

Everything! Recorded
All Books MultiMedia
All books (words)
.Movie
A Photo
A Book
24 Yecto, 21 zepto, 18 atto, 15 femto, 12 pico, 9
nano, 6 micro, 3 milli
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e-Science

• Data captured by instrumentsOr data generated by
  simulator
• Processed by software
• Placed in a files or database
• Scientist analyzes files / database
• Virtual laboratories
• Networks connecting e-Scientists
• Strong support from funding agencies
• Better use of resources
• Primitive today

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The Big Picture
Experiments Instruments
facts
questions
?
facts
Other Archives
answers
facts
Literature
facts
Simulations
The Big Problems

• Data ingest
• Managing a petabyte
• Common schema
• How to organize it?
• How to reorganize it
• How to coexist with others

• Query and Vis tools
• Support/training
• Performance
• Execute queries in a minute
• Batch query scheduling

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e-Science is Data Mining

• There are LOTS of data
• people cannot examine most of it.
• Need computers to do analysis.
• Manual or Automatic Exploration
• Manual person suggests hypothesis, computer
  checks hypothesis
• Automatic Computer suggests hypothesis person
  evaluates significance
• Given an arbitrary parameter space
• Data Clusters
• Points between Data Clusters
• Isolated Data Clusters
• Isolated Data Groups
• Holes in Data Clusters
• Isolated Points

Nichol et al. 2001 Slide courtesy of and adapted
from Robert Brunner _at_ CalTech.
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Data Analysis

• Looking for
• Needles in haystacks the Higgs particle
• Haystacks Dark matter, Dark energy
• Needles are easier than haystacks
• Global statistics have poor scaling
• Correlation functions are N2, likelihood
  techniques N3
• As data and computers grow at same rate, we can
  only keep up with N logN
• A way out?
• Discard notion of optimal (data is fuzzy,
  answers are approximate)
• Dont assume infinite computational resources or
  memory
• Requires combination of statistics computer
  science

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TerraServer/TerraServicehttp//terraService.Net/

• US Geological Survey Photo (DOQ) Topo (DRG)
  images online.
• On Internet since June 1998
• Operated by Microsoft Corporation
• Cross Indexed with
• Home sales,
• Demographics,
• Encyclopedia
• A web service
• 20 TB data source
• 10 M web hits/day

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USGS Image Data

• Digital Raster Graphics
• 1 TB compressed TIFF, 65,000 files
• Scanned topographic maps
• 100 U.S. coverage
• 124,000, 1100,000 and 1250,000 scale maps
• Maps vary in age

• Digital OrthoQuads
• 18 TB, 260,000 files uncompressed
• Digitized aerial imagery
• 88 coverage conterminous US
• 1 meter resolution
• lt 10 years old

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User Interface Concept
Display Imagery 316 m 200 x 200 pixel images 7
level image pyramid Resolution 1 meter/pixel to
64 meter/pixel Navigation Tools 1.5 m place
names Click-on Coverage map Longitude and
Latitude search U.S. Address Search External
Geo-Spatial Links to USGS On-line Stream
Gauges Home Advisor Demographics Home Advisor
Real Estate Encarta Articles Steam flow gauges
Concept User navigates an almost seamless
image of earth
Click on image to zoom in
Buttons to pan NW, N, NE, W, E, SW, S, SE
Links to switch between Topo, Imagery, and Relief
data
Links to Print, Download and view meta-data
information
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Terra Service New Things

• A popular web service
• Exactly the map you want.
• Dynamic Map Re-projection
• UTM to Geographic projection
• Dynamic texture mapping?
• New Data
• 1 foot resolution natural color imagery
• Census Tiger data
• Lights Out Management
• MOM
• Auto-backup / restore on drive failure

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New Urban Area Data
Microsoft Campus at 4 meter resolution
Redundant Bunch 1
Ball field at .25 meter resolution
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TerraServer Becomes a Web ServiceTerraServer.net
-gt TerraService.Net

• Web server is for people.
• Web Service is for programs
• The end of screen scraping
• No faking a URL pass real parameters.
• No parsing the answer data formatted into your
  address space.
• Hundreds of users but a specific example
• US Department of Agriculture

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TerraServer Web Services
Terra-Tile-Service
Landmark-Service

• Get image meta-data
• Query TS Gazetteer
• Retrieve TS ImageTiles
• Projection conversions
• Web Map Client
• OpenGIS like
• Landmarks layered on TerraServer imagery

• Geo-coded data of well-known objects (points),
  e.g. Schools, Golf Courses, Hospitals, etc.
• Polygons of well-known objects (shapes), e.g. Zip
  Codes, Cities, etc
• Fat Map Client
• Visual Basic / C Windows Form
• Access Web Services for all data

Sample Apps
http//terraservice.net
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Web Services

• Web SERVER
• Given a url parameters
• Returns a web page (often dynamic)
• Web SERVICE
• Given a XML document (soap msg)
• Returns an XML document
• Tools make this look like an RPC.
• F(x,y,z) returns (u, v, w)
• Distributed objects for the web.
• naming, discovery, security,..
• Internet-scale distributed computing

Your program
Web Server
http
Web page
Your program
Web Service
soap
Data In your address space
objectin xml
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Terraserver Architecture
HTML
DB Server
Map UI Web Forms
Standard Browsers
Image/jpeg
668 m Rows
Map Server Http Handler
Smart Clients
SQL 20002.0 TB Db
TerraServer Web Service
Image/jpeg
WindowsForms
SQL 20002.0 TB Db
XML
.NET Framework
SQL 20002.0 TB Db
ADO.NET
OLEDB
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TerraServer Schema
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Load Process
Internet Data Center
2 TBDatabase
2 TBDatabase
2 TBDatabase
Read 4 Images
Write 1
TerraScale
CorporateNetwork
6 TB Staging Area
TerraCutter
ReadImageFiles
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TerraServer Hardware

• Storage Bricks
• White-box commodity servers
• 4tb raw / 2TB Raid1 SATA storage
• Dual Hyper-threaded Xeon 2.4ghz, 4GB RAM
• Partitioned Databases (PACS partitioned array)
• 3 Storage Bricks 1 TerraServer data
• Data partitioned across 20 databases
• More data partitions coming
• Low Cost Availability
• 4 copies of the data
• RAID1 SATA Mirroring
• 2 redundant Bunches
• Spare brick to repair failed brick 2N1 design
• Web Application bunch aware
• Load balances between redundant databases
• Fails over to surviving database on failure
• 100K capital expense.

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Research Objectives
User/App Goals
Technology Goals

• Test/show scalability
• Test/show availability
• Test/show lights out
• all operations maintenance occurs remotely
• Minimal ops and dev staff
• web service poster child

• Public Access to remote sensing data with no
  GIS expertise required
• Ubiquitous No special hw/sw required by client
• Delivery All OnLine/Internet Based, no tape or
  CD distribution
• Simple Designed to be used by a 6th grade
  geography student

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Virtual Observatoryhttp//www.astro.caltech.edu/n
voconf/http//www.voforum.org/

• Premise Most data is (or could be online)
• So, the Internet is the worlds best telescope
• It has data on every part of the sky
• In every measured spectral band optical, x-ray,
  radio..
• As deep as the best instruments (2 years ago).
• It is up when you are up.The seeing is always
  great (no working at night, no clouds no moons
  no..).
• Its a smart telescope links objects and
  data to literature on them.

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Why Astronomy Data?

• It has no commercial value
• No privacy concerns
• Can freely share results with others
• Great for experimenting with algorithms
• It is real and well documented
• High-dimensional data (with confidence intervals)
• Spatial data
• Temporal data
• Many different instruments from many different
  places and many different times
• Federation is a goal
• The questions are interesting
• How did the universe form?
• There is a lot of it (petabytes)

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Time and Spectral DimensionsThe Multiwavelength
Crab Nebulae
Crab star 1053 AD
X-ray, optical, infrared, and radio views of
the nearby Crab Nebula, which is now in a state
of chaotic expansion after a supernova explosion
first sighted in 1054 A.D. by Chinese Astronomers.
Slide courtesy of Robert Brunner _at_ CalTech.
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SkyServer.SDSS.org

• A modern archive
• Raw Pixel data lives in file servers
• Catalog data (derived objects) lives in Database
• Online query to any and all
• Also used for education
• 150 hours of online Astronomy
• Implicitly teaches data analysis
• Interesting things
• Spatial data search
• Client query interface via Java Applet
• Query interface via Emacs
• Popular -- 1 of Terraserver ?
• Cloned by other surveys (a template design)
• Web services are core of it.

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Demo of SkyServer

• Shows standard web server
• Pixel/image data
• Point and click
• Explore one object
• Explore sets of objects (data mining)

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Data Federations of Web Services

• Massive datasets live near their owners
• Near the instruments software pipeline
• Near the applications
• Near data knowledge and curation
• Super Computer centers become Super Data Centers
• Each Archive publishes a web service
• Schema documents the data
• Methods on objects (queries)
• Scientists get personalized extracts
• Uniform access to multiple Archives
• A common global schema

Federation
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Federation SkyQuery.Net

• Combine 4 archives initially
• Just added 10 more
• Send query to portal, portal joins data from
  archives.
• Problem want to do multi-step data analysis
  (not just single query).
• Solution Allow personal databases on portal
• Problem some queries are monsters
• Solution batch schedule on portal server,
  Deposits answer in personal database.

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SkyQuery Structure

• Each SkyNode publishes
• Schema Web Service
• Database Web Service

• Portal is
• Plans Query (2 phase)
• Integrates answers
• Is itself a web service

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SkyQuery http//skyquery.net/

• Distributed Query tool using a set of web
  services
• Four astronomy archives from Pasadena, Chicago,
  Baltimore, Cambridge (England).
• Feasibility study, built in 6 weeks
• Tanu Malik (JHU CS grad student)
• Tamas Budavari (JHU astro postdoc)
• With help from Szalay, Thakar, Gray
• Implemented in C and .NET
• Allows queries like

SELECT o.objId, o.r, o.type, t.objId FROM
SDSSPhotoPrimary o, TWOMASSPhotoPrimary t
WHERE XMATCH(o,t)lt3.5 AND AREA(181.3,-0.76,6.5)
AND o.type3 and (o.I - t.m_j)gt2
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SkyNode Basic Web Services

• Metadata information about resources
• Waveband
• Sky coverage
• Translation of names to universal dictionary
  (UCD)
• Simple search patterns on the resources
• Cone Search
• Image mosaic
• Unit conversions
• Simple filtering, counting, histogramming
• On-the-fly recalibrations

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Portals Higher Level Services

• Built on Atomic Services
• Perform more complex tasks
• Examples
• Automated resource discovery
• Cross-identifications
• Photometric redshifts
• Outlier detections
• Visualization facilities
• Goal
• Build custom portals in days from existing
  building blocks (like today in IRAF or IDL)

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MyDB added to SkyQuery

• Moves analysis to the data
• Users can cooperate (share MyDB)
• Still exploring this

• Let users add personal DB 1GB for now.
• Use it as a workbook.
• Online and batch queries.

MyDB
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The Big Picture
Experiments Instruments
facts
questions
?
facts
Other Archives
answers
facts
Literature
facts
Simulations
The Big Problems

• Data ingest
• Managing a petabyte
• Common schema
• How to organize it?
• How to reorganize it
• How to coexist with others

• Query and Vis tools
• Support/training
• Performance
• Execute queries in a minute
• Batch query scheduling

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Grid and Web Services Synergy

• I believe the Grid will be many web
  services share data (computrons are free)
• IETF standards Provide
• Naming
• Authorization / Security / Privacy
• Distributed Objects
• Discovery, Definition, Invocation, Object Model
• Higher level services workflow, transactions,
  DB,..
• Synergy commercial Internet Grid tools