cassandra + hadoop = brisk

Our sponsors:

Acunu

London

But first, a short back story…

NoSQL!

New Ad Targeting Product

Join

May 2010

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16 node cluster running smoothly!

Start meetup group

Learn, learn, learn

GC HELL!

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Hire a Java dev from

Cassandra London!

No Hive support CASSANDRA-913

No streaming Jar support

Pig support

Analytics

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Run out of speaker

volunteers

0.8 arrivesCounters

CQL

Not compatible

with 0.6

Have to watch the sales pitch

again!

Cassandra 0.7 released!Secondary indexes

Provide talks and beer!

More meetups…

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Please volunteer if you would like to give a talk, Internet

fame awaits

• My experience with Cassandra in production is positive

• Analytics is more difficult than it could be

• Welcome Brisk!

• Brisk combines Hadoop, Hive and Cassandra in a “distribution”

In a nutshell

• CassandraFS as HDFS compatible layer; no namenode, no SPOF

• Can split cluster for OLAP and OLTP workloads, scaling up either as required

Demonstrating brisk…

Building an Ad Network!

Demonstrating brisk…

Building an Ad Network!

The plan:

• Simple data model – segment users into buckets• System to put users in buckets via a pixel• Real-time queries• Analytics

We Have Your KidneysThe ad-network for the paranoid generation

• Cookie based identification• API provides:• Add user to a bucket (including ability to define expiry time)• Get buckets a user belongs to

Setup Briskhttp://www.datastax.com/docs/0.8/brisk/install_brisk_ami

• Step-by-step guide with pictures!• Ubuntu 10.10 image with RAID 0 ephemeral disks• Jairam has been bug-fixing some minor issues

Data model

CF = users[userUUID] [segmentID] = 1

CF = segments[segmentID] [userUUID] = 1

Data modelcreate keyspace whyk ... with placement_strategy = 'org.apache.cassandra.locator.SimpleStrategy' ... and strategy_options = [{replication_factor:1}];create column family users ... with comparator = 'AsciiType'... and rows_cached = 5000;create column family segments... with comparator = 'AsciiType'... and rows_cached = 5000;

Data modelcreate keyspace whyk ... with placement_strategy = 'org.apache.cassandra.locator.SimpleStrategy' ... and strategy_options = [{replication_factor:1}];create column family users ... with comparator = 'AsciiType'... and rows_cached = 5000;create column family segments... with comparator = 'AsciiType'... and rows_cached = 5000;

Our pixel

http://wehaveyourkidneys.com/add.php?segment=<alphaNumericCode>&expire=<numberOfSeconds>

• We’ll use Cassandra’s expiring columns feature

PHP code – uses phpcassa$pool = new ConnectionPool('whyk', array('localhost'));$users = new ColumnFamily($pool, 'users');$segments = new ColumnFamily($pool, 'segments');$users->insert( $userUuid, array($segment => 1), NULL, // default TS $expires );$segments->insert( $segment, array($userUuid => 1), NULL, // default TS $expires );

Real-time access

http://wehaveyourkidneys.com/show.php

$pool = new ConnectionPool('whyk', array('localhost'));$users = new ColumnFamily($pool, 'users');// @todo this only gets first 100!$segments = $users->get($userUuid);

header('Content-Type: application/json');echo json_encode(array_keys($segments));

Analytics

How many users in each segment?

Launch HIVE (very easy!)

root@brisk-01:~# brisk hive

CREATE EXTERNAL TABLE whyk.users(userUuid string, segmentId string,

value string)STORED BY 'org.apache.hadoop.hive.cassandra.CassandraStorageHandler’WITH SERDEPROPERTIES ("cassandra.columns.mapping" = ":key,:column,:value" );

select segmentId, count(1) as totalfrom whyk.usersgroup by segmentIdorder by total desc;

Summary

http://www.flickr.com/photos/sovietuk/2956044892/sizes/o/in/photostream/

Real time access+

Batch analytics

Easy

Easy to setupEasy to deploy mixed-mode

clustersEasy to query (Hive)

No Single Pointof Failure

Further reading…Installing the Brisk AMIhttp://www.datastax.com/docs/0.8/brisk/install_brisk_ami

Key advantages of Brisk – from Jonathan Ellishttp://hackerne.ws/item?id=2528271

Why I’m very excited about DataStax’s Brisk – by Nathan Milfordhttp://blog.milford.io/2011/04/why-i-am-very-excited-about-datastaxs-brisk/

The demo code on Githubhttps://github.com/davegardnerisme/we-have-your-kidneys