Explorys has been using HBase and Hadoop since HBase 0.20, and will walk through lessons learned over years of usage from their first HBase implementation through a series of upgrades and changes, including impacts to schema design, data loading, data indexing, data access and analytics, and operational processes.

1. © 2013 Experian Limited. All rights reserved.
HBaseCon 2013
Application Track – Case Study
Experian Marketing Services
ETL for HBase

2. © 2013 Experian Limited. All rights reserved.
Manoj Khanwalkar
Chief Architect
Experian Marketing Services, New York
Govind Asawa
Big Data Architect
Experian Marketing Services, New York
Who We Are

3. © 2013 Experian Limited. All rights reserved.
1. About Experian Marketing Services
2. Why HBase
3. Why custom ETL
4. ETL solution features
5. Performance
6. Case Study
7. Conclusion
Agenda

4. © 2013 Experian Limited. All rights reserved.
Experian Marketing Services
1 billion+
messages
daily
2000+
Institutional
clients
9 regions,
24/7
500+
Tetabytes of
data
200+ big
queries
2000+ data
export jobs
Email and
social digital
marketing
messages.
100% surge in
volume during
peak season
Across all
verticals
Platforms
operating
globally
Client needs 1 to
7 years of
marketing data
depending on
verticals
Complicated
queries on 200+
million records
400+ columns for
segmentation
Client needs
daily
incremental
activity data

5. © 2013 Experian Limited. All rights reserved.
• Traditional RDBMS based solution is very challenging and cost
prohibitive for the scale of operations
• In SaaS based multi-tenancy model we require schema flexibility to
support thousands of clients with their individual requirements
• In majority of cases key based lookups can satisfy data extraction
requirements (including range scans and filters) which is well supported by
HBase
• Automatic sharding and horizontally scalable
• HBase provides a Java API which can be integrated with Experian’s
other systems.
5
Why HBase

6. © 2013 Experian Limited. All rights reserved. 6
Why develop an Integrator toolkit?
Connectivity Environment Cost
• Ability to ingest and
read data from HBase
and MongoDB
• Connectors for cloud
computing
• Support for REST and
other industry standard
API’s
• Supports SaaS Model
• Dynamically handles
data input changes (# of
fields & new fields)
• Licensing
• Integrate with other
systems seamlessly thus
improving time to
market
• Resources required to
develop, administer and
maintain solution
• Major ETL vendors do not support HBase
• ETL solution needs extensive development if data structure changes which negates
advantages offered by No-SQL solution

7. © 2013 Experian Limited. All rights reserved. 7
Integrator Architecture
DataIngester
TargetSystems
Third Party
JMS
Database
SourceSystems
Connectors
CSV Reader
Processor
Event Listener
Message Broker
File Watcher
Parser Factory
Key Generator
Parser
Loader
RDBMS Loader
HBase Loader
Container
Metadata
Analyzer
Loader
Aggregator
RDBMS
HBase
Extractor
Query Output
Aggregate Aware
Stamping Transform
SaaS
JMS
Files
RDBMS
HBase
RDBMS
HBase
MongoDB

8. © 2013 Experian Limited. All rights reserved. 8
Extractor Architecture
HDFS
Integrator
Send Data Click Data Bounce Data TXN Data
Metadata Detailed data Aggregates
HBase
Web
Server
Reporting
Analytics
Extractor
Query
Optimizer

9. © 2013 Experian Limited. All rights reserved.
Data ingestion from multiple sources
• Flat files
• NO-SQL
• RDBMS (through JDBC)
• SaaS (Salesforce etc.)
• Messaging and any system providing events streaming
Ability to de-normalize fact table while ingesting data
• # of lookup tables can be configured
Near real time generation of aggregate table
• # of aggregate tables can be configured
• HBase counters are used to keep aggregated sum/count
• Concurrently aggregates can be populated in RDBMS of choice
9
Integrator & Extractor

10. © 2013 Experian Limited. All rights reserved.
Transformation of column value to another value
• Add column by transformation
• Drop columns from input stream if no persistence is required
Data filter capability
• Drop record while ingesting base table
• Drop record while aggregation
Aggregate aware optimized query execution
• Query Performance: Analyze column requested by user in query and determine based
on count table with minimum record which can satisfy this requirement.
• Transparent: No user intervention or knowledge of schema is required
• Optimizer: Conceptually similar to RDBMS query plan optimizer. Concept extended to
No-SQL databases
• Metadata Management: Integrated metadata with ETL process can be used by variety of
applications.
10
Integrator & Extractor

11. © 2013 Experian Limited. All rights reserved.
Framework
• Solution based on Spring as a light weight container and built a framework around it to
standardize on the lifecycle of the process and to enable any arbitrary functionality to
reside in the container by implementing a Service interface.
• The container runs in a batch processing or daemon mode.
• In the daemon mode , it uses the Java 7 File Watcher API to react to files placed in the
specified directory for processing.
Metadata catalogue
• Metadata about all HBase table in which data ingested is stored
• For each table primary key, columns and record counter is stored
• HBase count is brute force scan and expensive API call. This can be avoided if metadata is
published at the time of data ingestion
• Avoid expensive queries which can bring cluster to its knees
• Provide faster query performance
11
Integrator

12. © 2013 Experian Limited. All rights reserved.
• We used a 20 node cluster in production; each node had 24 cores with a
10GigE network backbone.
• We observed a throughput of 1.3 million records inserted in HBase per
minute per node.
• Framework allowed us to run ETL process on multiple machines thus
providing horizontal scalability.
• Most of our queries returned back in at most a few seconds.
12
Integrator – System Performance

13. © 2013 Experian Limited. All rights reserved.
• Our experience shows that HBase offers a cost effective and performance
solution for managing our data explosion while meeting the increasingly
sophisticated analytical and reporting requirements of clients.
• ETL framework allows us to leverage HBase and its features while
improving developer productivity.
• Framework gives us ability to roll out new functionality with minimum
time to market.
• Metadata catalogue optimizes query and improves cluster performance
• Select count() on big HBase table take minutes/hours and can bring
cluster to knees. Metadata of Integrator will give counts along with
PrimaryKey, Columns in milliseconds
13
Conclusion

14. © 2013 Experian Limited. All rights reserved.
• Case Study
14
Appendix

15. © 2013 Experian Limited. All rights reserved. 15
HBase Schema & Record
Client
ID
Campaign
ID
Time
logged
User
ID
Orig
domain
Rcpt
domain
DS
status
Bounce
cat
IP Time
queued
1 11 01/01/13 21 abc.com gmail.com success 192.168.
6.23
01/01/
2013
2 12 01/02/13 31 xyz.com yahoo.com success bad-
mailbox
112.168.
6.23
01/01/
2013
Fact Table  send
Send Record
client_id,campaign_id,time_logged,user_id,orig_domain,rcpt_domain,dsn_status,bounce_cat,ip,Time_queued
1,11,01/01/2013,21,abc.com,gmail.com,success,192.168.6.23,01/01/2013

16. © 2013 Experian Limited. All rights reserved. 16
HBase Schema & Record
Fact Table  activity
Activity Record
client_id,campaign_id,event_time,user_id,event_type
1,11,01/01/2013,21,open
Client
ID
Campaign
ID
Time
logged
User
ID
Orig
domain
Rcpt
domain
IP city Event
type
IP Send
time
1 11 01/01/13 21 abc.com gmail.com SFO Open 192.168.
6.23
01/01/
2013
2 12 01/04/13 31 xyz.com yahoo.com LA Click 112.168.
6.23
01/01/
2013

17. © 2013 Experian Limited. All rights reserved. 17
HBase Schema & Record
Dimension Table  demographics
Dimension Table  ip
Client ID User ID Date Age Gender State City Zip Country Flag
1 11 01/01/13 21 M CA SFO 94087 USA Y
2 12 01/02/13 31 M CA SFO 94087 USA N
IP Date Domain State Country City
192.168.6.23 01/01/2013 gmail.com CA USA SFO
112.168.6.23 01/02/2013 abc.edu NJ USA Newark

18. © 2013 Experian Limited. All rights reserved. 18
HBase Schema & Record
Aggregate Table  A1
Aggregate Table  A2
Campaign ID Date Gender State Country Count
11 01/01/13 M CA USA 5023
12 01/02/13 M CA USA 74890
Client ID Date Gender State Country Count
1 01/01/13 M CA USA 742345
2 01/02/13 M CA USA 1023456

19. © 2013 Experian Limited. All rights reserved. 19
Metadata
Metadata Table
Table Name Primary Key Columns Count
demographics Client_id,Campaig
n_id,Date
Client_id, Campaign_id, Date, Age,
Gender,State,City,Country,Flag
10,000,000
A1 Campaign_id,Date Campaign_id,Date,Gender,State,Country,Count 1,000,000
A2 Client_id,Date Client_id,Date,Gender,State,Country,Count 500,000

20. © 2013 Experian Limited. All rights reserved.
User Query without Extractor Aggregate Awareness
• Select client_id,state,count from demographics
• Query Execution: Query will be executed on demographics table which has
300,000,000 rows
User Query with Extractor Aggregate Awareness
• Select client_id,state,count from demographics
• Query Execution:
– Step 1: Extractor will parse list of columns from query
– Step 2: Extractor will find list of tables which has these columns. In this example
extractor will get 2 tables demographics and A1 which can satisfy this query request
– Step 3: Extractor will decide which is best table to satisfy this query. This decision
will be based on # of rows in table. In this example table A1 has less # of rows
compared to table demographics so table A1 will be selected
– Step 4: Query will be executed against table A1 with appropriate where clause
specified by user
20
Query Execution in Action

21. © 2013 Experian Limited. All rights reserved.
• Bloom filters were enabled at the row level to enable HBase to skip
files efficiently.
• We used HBase filters extensively in the Scans to filter out as much
data as possible on the server side.
• Defined Aggregates judiciously to be able to respond to queries
without requiring HBase to resort to large file scans..
• We used a key concatenation that aligned to expected search
patterns to enable HBase to provide an exact match or do efficient
key range scans when a partial key was provided.
21
HBase Design Considerations

22. © 2013 Experian Limited. All rights reserved.
• We didn’t use MapReduce in our ETL framework for
following considerations
– Overhead of MapReduce based processes.
– Real-time access to data
– Every file had different header metadata , in MapReduce
we had difficulty in passing header metadata to each Map
process
– Avoid intermediate reads and writes to the HDFS file
system.
22
HBase Design Considerations

23. © 2013 Experian Limited. All rights reserved.
• We broke the Input and Output processing into separate threads and
allocated a lot more threads for output processing to compensate for
the relative processing speeds.
• Batched the Writes to HBase to reduce number of calls to the server
• Turned off the WAL in HBase , since we could always reprocess the file
in case of a rare failure
• Used primitives and Arrays in the code where feasible instead of Java
Objects and Collections, to reduce the memory footprint and the
pressure on the Garbage collector.
23
HBase Tuning

24. © 2013 Experian Limited. All rights reserved.
• Increased the Client Write Buffer size to several megabytes.
• To avoid hotspots and best data retrieval we designed composite
primary key. Key design allowed us to access data by providing exact
key or range scan by leading portion of key.
• We found that too many filters for scan provides diminishing returns
and after some point it degrades the overall scan performance
24
HBase Tuning

25. © 2013 Experian Limited. All rights reserved.
Thank you
For more information, please contact
Manoj Khanwalkar
Chief Architect
manoj.khanwalkar@experian.com
Govind Asawa
Big Data Architect
govind.asawa@experian.com