Upgrade to Pro
— share decks privately, control downloads, hide ads and more …
Speaker Deck
Features
Speaker Deck
PRO
Sign in
Sign up for free
Search
Search
Convergent Replicated Data Types
Search
Patrick Van Stee
December 14, 2012
Programming
4
760
Convergent Replicated Data Types
Patrick Van Stee
December 14, 2012
Tweet
Share
More Decks by Patrick Van Stee
See All by Patrick Van Stee
Raft: Consensus for Rubyists
vanstee
140
7k
Elixir and Ecto
vanstee
5
930
Bootstrap
vanstee
8
780
HTTP API Design for iOS Applications
vanstee
11
630
Consensus: An Introduction to Raft
vanstee
22
3k
Pour Over Brewing Method
vanstee
1
350
Celluloid & DCell
vanstee
4
550
Map Reduce & Ruby
vanstee
10
800
Other Decks in Programming
See All in Programming
Python型ヒント完全ガイド 初心者でも分かる、現代的で実践的な使い方
mickey_kubo
1
200
Advanced Micro Frontends: Multi Version/ Framework Scenarios @WAD 2025, Berlin
manfredsteyer
PRO
0
380
The Evolution of Enterprise Java with Jakarta EE 11 and Beyond
ivargrimstad
0
200
Claude Code + Container Use と Cursor で作る ローカル並列開発環境のススメ / ccc local dev
kaelaela
12
6.9k
Deep Dive into ~/.claude/projects
hiragram
14
12k
NPOでのDevinの活用
codeforeveryone
0
880
MCPを使ってイベントソーシングのAIコーディングを効率化する / Streamlining Event Sourcing AI Coding with MCP
tomohisa
0
160
20250708_JAWS_opscdk
takuyay0ne
2
120
新メンバーも今日から大活躍!SREが支えるスケールし続ける組織のオンボーディング
honmarkhunt
5
8.4k
NEWT Backend Evolution
xpromx
1
120
AI コーディングエージェントの時代へ:JetBrains が描く開発の未来
masaruhr
1
200
PostgreSQLのRow Level SecurityをPHPのORMで扱う Eloquent vs Doctrine #phpcon #track2
77web
2
570
Featured
See All Featured
Unsuck your backbone
ammeep
671
58k
What's in a price? How to price your products and services
michaelherold
246
12k
Building a Scalable Design System with Sketch
lauravandoore
462
33k
The Language of Interfaces
destraynor
158
25k
YesSQL, Process and Tooling at Scale
rocio
173
14k
A designer walks into a library…
pauljervisheath
207
24k
For a Future-Friendly Web
brad_frost
179
9.8k
Bash Introduction
62gerente
613
210k
GraphQLとの向き合い方2022年版
quramy
49
14k
jQuery: Nuts, Bolts and Bling
dougneiner
63
7.8k
[RailsConf 2023] Rails as a piece of cake
palkan
55
5.7k
Fashionably flexible responsive web design (full day workshop)
malarkey
407
66k
Transcript
Convergent Replicated Data Types
@vanstee
[email protected]
Patrick Van Stee
“Structuring data so conflict resolution is automatic”
Dynamo Trade consistency for availability and partition tolerance
Node 1 Node 2 { a: “200” } { a:
“-3000” } :(
Node 1 Node 2 { a: “200” } { a:
“-3000” } { a: “200”, a: “-3000” } Riak
CRDT •Counter •Set •Graph •List •Tree
CRDT •Counter •Set •Graph •List •Tree
Counter •Can only be increased •Merge: use largest value
Chat Room Karma Fault-Tolerant Distributed
Serious Business { SB[PVS]: 0} Serious Coding { SB[PVS]: 1}
# PVS++ { SC[PVS]: 0} { SC[PVS]: 5} # PVS += 5 { SB[PVS]: 2} # PVS++ Merge { SB[PVS]: 2, SC[PVS]: 5} { SB[PVS]: 1, SC[PVS]: 5} { SB[PVS]: 2, SC[PVS]: 5} { PVS: 7}
What about decrements? Use separate counters for positive and negative.
Take the difference for the result.
Serious Business { SB[PVS+]: 0, SB[PVS-]: 0 } Serious Coding
{ SB[PVS+]: 1, SB[PVS-]: 0 } # PVS++ { SB[PVS+]: 0, SB[PVS-]: 0 } { SB[PVS+]: 5, SB[PVS-]: 0 } # PVS += 5 { SB[PVS+]: 1, SB[PVS-]: 1 } # PVS-- Merge { PVS+: 6, PVS-: 1 } { PVS+: 6, PVS-: 0 } { PVS+: 6, PVS-: 1 } { PVS: 5 }
Set •Can only be added to •Merge: take the union
Serious Business { PVS: [ ] } Serious Coding {
PVS: [] } { PVS: [] } { PVS: [ ] } Merge { PVS: [ , ] } { PVS: [ , ] } { PVS: [ , , ] } { PVS: [ , , ] }
Hold on, Can we remove stuff? Use separate sets for
added and removed elements.
Serious Business { PVS+: [ ], PVS-: [] } Serious
Coding { PVS+: [], PVS-: [] } { PVS+: [], PVS-: [] } { PVS+: [ ], PVS-: [] } Merge { PVS+: [ , ], PVS-: [ ] } { PVS+: [ ], PVS-: [ ] } { PVS+: [ , ], PVS-: [] } { PVS+: [ , ], PVS-: [ ] } { PVS: [ ] }
But wait, we can only remove once?
U-Set •Append unique values to all set members •Garbage collection
becomes an issue
basho/riak_dt Demo
Use Cases •Like button •Page Views •Shopping Cart
Reference •INRIA paper •basho/riak_dt •RICON talk
Beginning Ruby on Rails Course bignerdranch.com/classes/beginning_ruby_on_rails