GDS: Genium Data Store Real Time, Low Latency, Reliable!

Iuliia Proskurnia!EMDC!KTH!2013!

2!

3!

4!

3900 companies! 39 countries! over 1500 corporate products!

USE CASE!

Write events!Retrieve ranges of records!

5!

Fault-Tolerant?!

Consistent?!

Fast?!

Scalable?!

6!

Approaches

!   Consensus based!

!   ...!!   Total Order Multicast!

!   Symmetric!

!   Token Site !

Uniform Reliable Total Order

◦  Validity !

◦  Uniform Integrity !

◦  Uniform Agreement !

◦  Uniform Total Order !

!

7!

8!

Genium INET Message Bus �Uniform Reliable Total Order Multicast

!   Similar to Amoeba protocol!

!  However... Fault Tolerant!!

9!

GDS: Genium Data Store

!   Uses Genium INET Message Bus abstraction!

!   Clients, Sequencer, Data store!

! Rewinders and sequencer replication!

!   Active replication!

Client!

Data store node!

Data store node!

10!

GDS high level abstraction

LEDS!

11!

LEDS

!   Column based!

!   BLOBS!

!   Appends!

!   Range Queries!

!  Not Distributed!

!  Not fault-tolerant!

12!

Properties

!   Consistent!

!   Failure Resilient!!   Replication!

!   Rewinders!

!   Cite Replication!

Total Order!

13!

Possible Failure Scenarios C

lient

Fai

lure!

Sequ

ence

r Fai

lure!

���8VHU

6HT

'6

���

>Q@

>Q@

:RUN

>Q��@

&XUUHQW�0HVVDJH��>Q��@ 5HZLQG�0HVVDJH��>Q@

���8VHU

6HT

'6

��� 5HZLQG�0HVVDJH��>Q@

6HT6WDQG%\

>Q@

>Q@

>Q@

>Q��@

3ULPDU\�3�

���

3

>Q@

>Q@

>Q@

5HZLQG�0HVVDJH��>Q@

14!

Scalability

!  Natural Load Balancing!

!   Partitioning (manual)!

15!

Evaluation

!   Inserts (throughput/latency)!

!   Range Queries (throughput)!

!   Range transmission failure!

16!

Set Up

17!

Writes �Throughput

18!

Writes Limits

19!

Writes �Latency

20!

Range Queries �Throughput

21!

Range Queries �Scalability

8 Concurrent Users!

22!

Range Queries �Link Failure

23!

Summary

!   uniform reliable total order multicast !

!   scales fine!

!   low latency!

!   consistent, fault-tolerant!

24!

Future Work

!   Generality!

!   Send compressed chunks!

!   Automated partitioning!

!   Long-running tests!

25!

Comments? Questions?

Thesis Writing Process!

26!

Single record read�without load

27!

Single record read�with load (10 000 inserts)

28!

Single record read�scalability

29!

Discussion