How to run Apache Cassandra over an IaaS of a distributed organization? What are the challenges we can solve with Cassandra? One of the tool for measuring replication latency can be found here: https://github.com/gitaroktato/cassandra-replication-latency-tools

1. Cassandra on
EPAM Cloud
Database deployed in multiple locations

2. AGENDA
• Typical issues with RDBMS
• Solutions with Cassandra
• Cassandra on EPAM Cloud

3. ABOUT ME
Oresztész Margaritisz
• Java CC member since 2015
• Distributed / Cloud Computing
• NoSQL
• Agile
• DevOps
@gitaroktato gitaroktato https://www.linkedin.com/in/oreszteszgitaroktato

4. TYPICAL ISSUES WITH RDBMS

5. TYPICAL ISSUES WITH RDBMS
• EPAM needs global delivery of services
• 25 countries
• 4 continents
• 19,600 employees
• Data storage with traditional RDBMS can be cumbersome
• Configuration issues
• Migrating data between locations can be hard
• Master - Slave configuration in local site gives tradeoff in performance

6. ARE WE SOLVING
THE SAME PROBLEM?

7. LATENCY AROUND THE GLOBE

8. LATENCY FOR 100 REQUESTS
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
1 request 100 requests
10 ms 1 second

9. BANDWIDTH VS. LATENCY

10. TYPICAL MULTI-MASTER MYSQL DEPLOYMENT
Master
1
Slave
1.1
Slave
1.2
Slave
1.3
Master
2
Slave
2.1
Slave
2.2
Slave
2,3
Master-Master
Replication

11. WE NEED NOSQL?

12. Dude, you need NoSQL!
ACID vs. BASE

13. WHY CASSANDRA?

14. CLIENT CONNECTIVITY
R/W
Client
R/W
Client

15. MULTI-REGION DEPLOYMENT
TokyoMinsk
Client

16. TUNABLE CONSISTENCY
Client

17. RAPID READ PROTECTION
Client

18. CASSANDRA ON EPAM CLOUD

19. INITIATIVE BY RND TEAM @ JAVACC

20. WE NEED YOU!

21. CONFIGURATION GUIDE

22. CONFIGURATION GUIDE
AWS-AP-NORTHEASTEPAM-BY1
cassandra-rackdc.properties
dc=AWS-AP-NORTHEAST
rack=rack1
prefer_local=true
Public IP
cassandra.yaml
endpoint_snitch:
GossipingPropertyFileSnitch
cassandra-rackdc.properties
dc=EPAM-BY1
rack=rack1
prefer_local=true
cassandra.yaml
broadcast_address: <PUBLIC_IP>
cassandra.yaml
seed_provider:
- class_name: org.apache.cassandra.locator.SimpleSeedProvider
- seeds: <AWS_SEED_PUBLIC_IP>
cassandra.yaml
...
- seeds: <BY1_SEED_PUBLIC_IP>

23. BOOT SEQUENCE
AWS-AP-NORTHEASTEPAM-BY1
CREATE KEYSPACE replicated WITH REPLICATION = { 'class' : 'NetworkTopologyStrategy',
'EPAM-BY1' : 2, 'AWS-AP-NORTHEAST' : 2 };

24. CAPACITY PLANNING
• Replication latency between regions
• Transactions per second for the whole cluster
• 3 MEDIUM instance in EPAM-BY1
• 3 MEDIUM instance in AWS-AP-NORTHEAST

25. REPLICATION LATENCY
Client
Client
WRITE
READ
Client
WRITE
READ
NTP

26. REPLICATION LATENCY
0 50 100 150 200 250 300 350 400
TCP Ping
DC1 -> DC2
Single Client
Average 99% Max

27. CLUSTER THROUGHPUT
0 5000 10000 15000 20000 25000 30000
LOCAL_QUORUM
Replication: 2
LOCAL_ONE
Replication: 2
LOCAL_ONE
Replication: 1
node #1 node #2 node #3 SUM

30. SUMMARY
• Configuration is easy
• Migrating data between locations is built-in
• Load spread evenly
• Dealing with network failures by default

31. UP NEXT
• Real migration use-case
• Performance tuning

32. LOOKING FOR A REAL MIGRATION USE-CASE
KB Page
https://kb.epam.com/display/EJAVACC/Multi+datacenter+setup+with+NoSQL
Dzmitry Skaredau - Dzmitry_Skaredau@epam.com
Oresztesz Margaritisz - Oresztesz_Margaritisz@epam.com

33. References
EPAM Project Space
https://kb.epam.com/display/EJAVACC/Multi-Region+Cassandra+set-up+in+EPAM+Cloud
Latency: The Next Web Performance Bottleneck
https://www.igvita.com/2012/07/19/latency-the-new-web-performance-bottleneck/
More Bandwdth Doesn’t Matter
https://docs.google.com/a/chromium.org/viewer?a=v&pid=sites&srcid=Y2hyb21pdW0ub3JnfGRldnxne
DoxMzcyOWI1N2I4YzI3NzE2

34. References pt. 2
Cassandra’s Rapid Read Protection
http://www.datastax.com/dev/blog/rapid-read-protection-in-cassandra-2-0-2