Why we built a distributed system - DSConf 2018

Talk co-presented with @brewkode at DSConf 2018.

Video - https://www.youtube.com/watch?v=zSgxt9JsTPg&index=11&list=PLyMKpkdEV2csQg93bEPv2R27sawxIm9zG

Transcript

1. Why we built a distributed system DSConf 2018
2. Sriram Ramachandrasekaran Principal Engineer, Indix https://github.com/brewkode
3. 1B+ Products 67K+ Brands 2.5B+ Offers 6K+ Categories
4. Crawl Parse Dedup Classify Extract Match Index Data Pipeline @ Indix
5. Crawl Parse Dedup Classify Extract Match Index Data Pipeline @ Indix
6. Desirable Properties • Handle Scale - order of TBs • Fault Tolerant • Operability
7. Traditionally... • Tiered architecture • Scale individual tiers • Until...
8. Traditionally... • Tiered architecture • Scale individual tiers ◦ Web Tier ◦ Service Tier • Until...
9. Traditionally... • Tiered architecture • Scale individual tiers ◦ Web Tier ◦ Service Tier • Until...
10. Essentially, we are looking to Scale data systems
11. BigTable, 2006 Dynamo, 2007 Cassandra, 2008 Voldemort, 2009 rise of KV Stores distributed, replicated, fault-tolerant, sorted*
12. Service Service Service Distributed Data Store
13. Service Service Service Distributed Data Store Latency
14. Distributed Service
15. Distributed Service Data locality kills latency Increases Application Complexity
16. Just having a distributed store isn’t enough! We need something more...
17. boils down to... Distributed Data Store + CoProcessors (Bigtable / HBase) …run arbitrary code “next” to each shard
18. Distributed Data Store + CoProcessors (Bigtable / HBase) - Business logic upgrade is painful - CoProcessors are not services, more an afterthought - Failure semantics are not well established - More applications means multiple coproc or single bloated coproc - Noisy neighbours / Impedance due to a shared datastore
19. Applications need to OWN Scaling
20. In-house Vs Off-the-shelf In-house Off-the-shelf Features Subset Superset Moving parts Fully Controllable Community Controlled Ownership Implicit Acquired / Cultural Upfront cost High Low Expertise Hired / Retained / Nurtured Community
21. Ashwanth Kumar Principal Engineer, Indix https://github.com/ashwanthkumar
22. पांग ப Communication key=”foo” key=”bar” key=”baz” Request Routing Sync / Async Replication Replication Data Sharding Cluster Membership Primitives in a Distributed System
23. Introducing Suuchi DIY kit for building distributed systems github.com/ashwanthkumar/suuchi
24. Suuchi Provides support for ... - underlying communication channel - routing queries to appropriate member - detecting your cluster members - replicating your data based on your strategy - local state via embedded KV store per node (optionally) github.com/ashwanthkumar/suuchi
25. Communication + HandleOrForward + Scatter Gather uses http/2 with streaming
26. Sharding / Routing + Consistent Hash Ring - Your own sharding technique? node 2 node 1 node 3 node 4 Consistent hashing and random trees: Distributed caching protocols for relieving hot spots on the World Wide Web
27. Sharding / Routing + Consistent Hash Ring - Your own sharding technique? node 2 node 1 node 3 node 4 Consistent hashing and random trees: Distributed caching protocols for relieving hot spots on the World Wide Web
28. Sharding / Routing + Consistent Hash Ring - Your own sharding technique? node 2 node 1 node 3 node 4 Consistent hashing and random trees: Distributed caching protocols for relieving hot spots on the World Wide Web
29. Sharding / Routing + Consistent Hash Ring - Your own sharding technique? Consistent hashing and random trees: Distributed caching protocols for relieving hot spots on the World Wide Web node 2 node 3 node 4
30. Membership static dynamic fault tolerance in case of node/process failure scaling up/down needs downtime of the system
31. Replication Provides high availability for write heavy systems at the cost of consistency sync async* every request is successful only if all the replicas succeeded
32. Storage + KeyValue + RocksDB - Your own abstraction? embedded KV store from FB for server workloads
33. Suuchi @ Indix • HTML Archive ◦ Handles 1000+ tps - write heavy system ◦ Stores 120 TB of url & timestamp indexed HTML pages • Stats (as Monoids) Aggregation System ◦ Approximate real-time aggregates ◦ Timeline & windowed queries • Real time scheduler for our Crawlers ◦ Prioritising which next batch of urls to crawl ◦ Helps crawl 20+ million urls per day
34. Ringpop from Uber, 2015 Gizzard from Twitter, 2011 Slicer from Google, 2016 Suuchi, 2016 Idea behind Suuchi Membership, Request Routing, Sharding etc.
35. Thank you