dreamforce_2012_hadoop_use_cases
TRANSCRIPT
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How Salesforce.com Uses HadoopHow Salesforce.com Uses HadoopSome Data Science Use Cases
Narayan Bharadwaj Jed Crosby
salesforce.com salesforce.com
@nadubharadwaj @JedCrosby
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Safe HarborSafe harbor statement under the Private Securities Litigation Reform Act of 1995: This presentation may contain forward-looking statements that involve risks, uncertainties, and assumptions. If any such uncertainties materialize or if any of the assumptions proves incorrect, the results of salesforce.com, inc. could differ materially from the results expressed or implied by the forward-looking statements we make. All statements other than statements of historical fact could be deemed forward-looking, including any projections of product or service availability, subscriber growth, earnings, revenues, or other financial items and any statements regarding strategies or plans of management for future operations, statements of belief, any statements concerning new, planned, or upgraded services or technology developments and customer contracts or use of our services. The risks and uncertainties referred to above include – but are not limited to – risks associated with developing and delivering new functionality for our service, new products and services, our new business model, our past operating losses, possible fluctuations in our operating results and rate of growth, interruptions or delays in our Web hosting, breach of our security measures, the outcome of intellectual property and other litigation, risks associated with possible mergers and acquisitions, the immature market in which we operate, our relatively limited operating history, our ability to expand, retain, and motivate our employees and manage our growth, new releases of our service and successful customer deployment, our limited history reselling non-salesforce.com products, and utilization and selling to larger enterprise customers. Further information on potential factors that could affect the financial results of salesforce.com, inc. is included in our annual report on Form 10-Q for the most recent fiscal quarter ended July 31, 2012. This documents and others containing important disclosures are available on the SEC Filings section of the Investor Information section of our Web site. Any unreleased services or features referenced in this or other presentations, press releases or public statements are not currently available and may not be delivered on time or at all. Customers who purchase our services should make the purchase decisions based upon features that are currently available. Salesforce.com, inc. assumes no obligation and does not intend to update these forward-looking statements.
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Agenda
• Technology
• Hadoop use cases
• Use case discussion• Product Metrics
• User Behavior Analysis
• Collaborative Filtering
• Q&A
Every time you see the elephant, we will attempt to explain a Hadoop related concept.
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Got “Cloud Data”?
800 million transactions/dayTerabytes/day
130k customersMillions of users
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Technology
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Hadoop Overview
- Started by Doug Cutting at Yahoo!
- Based on two Google papers Google File System (GFS): http://research.google.com/archive/gfs.html
Google MapReduce: http://research.google.com/archive/mapreduce.html
- Hadoop is an open source Apache project Hadoop Distributed File System (HDFS)
Distributed Processing Framework (MapReduce)
- Several related projects HBase, Hive, Pig, Flume, ZooKeeper, Mahout, Oozie, HCatalog
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Our Hadoop Ecosystem
Apache Pig
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Contributions
@pRaShAnT1784 : Prashant Kommireddi
Lars Hofhansl @thefutureian : Ian Varley
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Use Cases
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Product Metrics User behavior analysis Capacity planning
Monitoring intelligence Collections Query Runtime
Prediction
Early Warning System Collaborative Filtering Search Relevancy
Internal AppInternal App Product featureProduct feature
Hadoop Use Cases
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Product Metrics
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Track feature usage/adoption across 130k+ customers Eg: Accounts, Contacts, Visualforce, Apex,…
Track standard metrics across all features Eg: #Requests, #UniqueOrgs, #UniqueUsers, AvgResponseTime,…
Track features and metrics across all channels API, UI, Mobile
Primary audience: Executives, Product Managers
Product Metrics – Problem Statement
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Feature Metadata(Instrumentation)
Daily Summary(Output)
Crunch it(How?)
Storage & Processing
Feature (What?)Fancy UI
(Visualize)
Data Pipeline
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Feature Metrics (Custom Object) Feature Metrics (Custom Object)
Trend Metrics(Custom Object)Trend Metrics(Custom Object)
Client Machine Client Machine
Pig script generatorPig script generator
HadoopHadoop Log FilesLog Files
Lo
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User Input(Page Layout)
User Input(Page Layout) Reports, DashboardsReports, Dashboards
AP
IA
PI
AP
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Java ProgramJava Program
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Product Metrics Pipeline
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Id Feature Name PM Instrumentation Metric1 Metric2 Metric3 Metric4 Status
F0001 Accounts John /001 #requests #UniqOrgs #UniqUsers AvgRT Dev
F0002 Contacts Nancy /003 #requests #UniqOrgs #UniqUsers AvgRT Review
F0003 API Eric A #requests #UniqOrgs #UniqUsers AvgRT Deployed
F0004 Visualforce Roger V #requests #UniqOrgs #UniqUsers AvgRT Decom
F0005 Apex Kim axapx #requests #UniqOrgs #UniqUsers AvgRT Deployed
F0006 Custom Objects Chun /aXX #requests #UniqOrgs #UniqUsers AvgRT Deployed
F0008 Chatter Jed chcmd #requests #UniqOrgs #UniqUsers AvgRT Deployed
F0009 Reports Steve R #requests #UniqOrgs #UniqUsers AvgRT Deployed
Feature Metrics (Custom Object)
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Feature Metrics (Custom Object)
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User Input (Page Layout)Formula Field
Workflow Rule
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User Input (Child Custom Object)
Child Objects
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Apache Pig
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-- Define UDFs
DEFINE GFV GetFieldValue(‘/path/to/udf/file’);
-- Load data
A = LOAD ‘/path/to/cloud/data/log/files’ USING PigStorage();
-- Filter data
B = FILTER A BY GFV(row, ‘logRecordType’) == ‘U’;
-- Extract Fields
C = FOREACH B GENERATE GFV(*, ‘orgId’), LFV(*. ‘userId’) ……..
-- Group
G = GROUP C BY ……
-- Compute output metrics
O = FOREACH G {
orgs = C.orgId; uniqueOrgs = DISTINCT orgs;
}
-- Store or Dump results
STORE O INTO ‘/path/to/user/output’;
Basic Pig Script Construct
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Java Pig Script Generator (Client)
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Id Date #Requests #Unique Orgs #Unique Users Avg ResponseTime
F0001 06/01/2012 <big> <big> <big> <little>
F0002 06/01/2012 <big> <big> <big> <little>
F0003 06/01/2012 <big> <big> <big> <little>
F0001 06/02/2012 <big> <big> <big> <little>
F0002 06/02/2012 <big> <big> <big> <little>
F0003 06/03/2012 <big> <big> <big> <little>
Trend Metrics (Custom Object)
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Upload to Trend Metrics (Custom Object)
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Visualization (Reports & Dashboards)
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Visualization (Reports & Dashboards)
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Collaborate, Iterate (Chatter)
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Feature Metrics (Custom Object) Feature Metrics (Custom Object)
Trend Metrics(Custom Object)Trend Metrics(Custom Object)
Client Machine Client Machine
Pig script generatorPig script generator
HadoopHadoop Log FilesLog Files
Lo
g P
ull
Lo
g P
ull
User Input(Page Layout)
User Input(Page Layout) Reports, DashboardsReports, Dashboards
AP
IA
PI
AP
IA
PIW
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flo
wW
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flo
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Java ProgramJava Program
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Recap
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User Behavior Analysis
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Problem Statement
How do we reduce number of clicks on the user interface?
Need to understand top user click paths. What are they typically trying to do?
What are the user clusters/personas?
Approach:
• Markov transition for click path, D3.js visuals
• K-means (unsupervised) clustering for user groups
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Markov Transitions for "Setup" Pages
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K-means clustering of "Setup" Pages
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Collaborative Filtering
Jed Crosby
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Show similar files within an organization Content-based approach
Community-base approach
Collaborative Filtering – Problem Statement
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Popular File
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Related File
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Amazon published this algorithm in 2003. Amazon.com Recommendations: Item-to-Item Collaborative Filtering, by
Gregory Linden, Brent Smith, and Jeremy York. IEEE Internet Computing,
January-February 2003.
At Salesforce, we adapted this algorithm for Hadoop, and we use
it to recommend files to view and users to follow.
We found this relationship using item-to-item collaborative filtering
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Annual ReportVision Statement
Dilbert Comic
Darth Vader Cartoon
Disk Usage Report
Example: CF on 5 files
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Annual Report
Vision Statement
Dilbert Cartoon
Darth Vader Cartoon
Disk Usage Report
Miranda (CEO)
1 1 1 0 0
Bob (CFO) 1 1 1 0 0
Susan (Sales)
0 1 1 1 0
Chun (Sales) 0 0 1 1 0
Alice (IT) 0 0 1 1 1
View History Table
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Annual Report
Disk Usage Report
Darth Vader Cartoon
Dilbert Cartoon
Vision Statement
Relationships Between the Files
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Annual Report
Disk Usage Report
Darth Vader Cartoon
Dilbert Cartoon
Vision Statement2
2
0
0
31
0
3
1 1
Relationships Between the Files
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Annual Report
Vision Statement
Dilbert Cartoon
Darth Vader Cartoon
Disk Usage Report
Dilbert (2) Dilbert (3) Vision Stmt. (3) Dilbert (3) Dilbert (1)
Vision Stmt. (2) Annual Rpt. (2) Darth Vader (3) Vision Stmt. (1) Darth Vader (1)
Darth Vader (1) Annual Rpt. (2) Disk Usage (1)
Disk Usage (1)
The popularity problem: notice that Dilbert appears first in every list. This is probably not what we want.
The solution: divide the relationship tallies by file popularities.
Sorted Relationships for Each File
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Annual Report
Disk Usage Report
Darth Vader CartoonDilbert Cartoon
Vision Statement.82
.630
0
.77.33
0
.77
.45 .58
Normalized Relationships Between the Files
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Annual Report Vision Statement
Dilbert Cartoon
Darth Vader Cartoon
Disk Usage Report
Vision Stmt.(.82)
Annual Report (.82)
Darth Vader(.77)
Dilbert (.77)Darth Vader(.58)
Dilbert (.63) Dilbert (.77)Vision Stmt.(.77)
Disk Usage(.58)
Dilbert(.45)
Darth Vader (.33)
Annual Report(.63)
Vision Stmt.(.33)
Disk Usage(.45)
High relationship tallies AND similar popularity values now drive closeness.
Sorted relationships for each file, normalized by file popularities
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1) Compute file popularities
2) Compute relationship tallies and divide by file popularities
3) Sort and store the results
The Item-to-Item CF Algorithm
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MapReduce OverviewMap Shuffle Reduce
(adapted from http://code.google.com/p/mapreduce-framework/wiki/MapReduce)
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<user, file>
Inverse identity map
<file, List<user>>
Reduce
<file, (user count)>
Result is a table of (file, popularity) pairs that you store in the Hadoop distributed cache.
1. Compute File Popularities
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(Miranda, Dilbert), (Bob, Dilbert), (Susan, Dilbert), (Chun, Dilbert), (Alice, Dilbert)
Inverse identity map
<Dilbert, {Miranda, Bob, Susan, Chun, Alice}>
Reduce
(Dilbert, 5)
Example: File popularity for Dilbert
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<user, file>
Identity map
<user, List<file>>
Reduce
<(file1, file2), Integer(1)>, <(file1, file3), Integer(1)>, … <(file(n-1), file(n)), Integer(1)>
Relationships have their file IDs in alphabetical order to avoid double counting.
2a. Compute Relationship Tallies − Find All Relationships in View History Table
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(Miranda, Annual Report), (Miranda, Vision Statement), (Miranda, Dilbert)
Identity map
<Miranda, {Annual Report, Vision Statement, Dilbert}>
Reduce
<(Annual Report, Dilbert), Integer(1)>, <(Annual Report, Vision Statement), Integer(1)>, <(Dilbert, Vision Statement), Integer(1)>
Example 2a: Miranda’s (CEO) File Relationship Votes
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<(file1, file2), Integer(1)>
<(file1, file2), List<Integer(1)>
Identity map
Reduce: count and divide by popularities
<file1, (file2, similarity score)>, <file2, (file1, similarity score)>
Note that we emit each result twice,one for each file that belongs to a relationship.
2b. Tally the Relationship Votes − Just a Word Count, Where Each Relationship Occurrence is a Word
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<(Dilbert, Vader), Integer(1)>,<(Dilbert, Vader), Integer(1)>, <(Dilbert, Vader), Integer(1)>
<(Dilbert, Vader), {1, 1, 1}>
Identity map
Reduce: count and divide by popularities
<Dilbert, (Vader, sqrt(3/5))>, <Vader, (Dilbert, sqrt(3/5))>
Example 2b: the Dilbert/Darth Vader Relationship
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<file1, (file2, similarity score)>
Identity map
<file1, List<(file2, similarity score)>>
Reduce
<file1, {top n similar files}>
Store the results in your location of choice
3. Sort and Store Results
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<Dilbert, (Annual Report, .63)>,<Dilbert, (Vision Statement, .77)>,<Dilbert, (Disk Usage, .45)>,<Dilbert, (Darth Vader, .77)>
Identity map
<Dilbert, {(Annual Report, .63), (Vision Statement, .77), (Disk Usage, .45), (Darth Vader, .77)}>
Reduce
<Dilbert, {Darth Vader, Vision Statement}> (Top 2 files)
Store results
Example 3: Sorting the Results for Dilbert
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Cosine formula and normalization trick to avoid the distributed
cache
Mahout has CF
Asymptotic order of the algorithm is O(M*N2) in worst case, but is
helped by sparsity.
Appendix
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Narayan BharadwajNarayan BharadwajDirector, Product Management
@nadubharadwaj
Jed CrosbyJed CrosbyData Scientist@JedCrosby
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