CMU 15-645 Distributed OLTP

OLTP v.s. OLAP

  • On-line Transaction Processing
    • Short-lived TX
    • Small footprint
    • Repetitive operation
  • On-line Analytical processing
    • Long running queries
    • Complex joins
    • Exploratory queries

Architectures:

  • Shared Everything -> Shared Memory -> Shared Disk -> Shared Nothing
    • Shared Nothing (Only via network): Easy to increase capacity and hard ensure consistency at the same time

Data Transparency

  • Partitioned (Sharding) v.s. Replicated
  • Horizontal Partitioning (Round-robin/Hash/Range)

Distributed Transactions

  • Centralized v.s. Decentralized

Distributed CC

  • Need to allow multi-TXs to execute simultaneously across multi-nodes
    • Factors: Replication, Network Communication Overhead, Node Failure, Clock skew
    • Atomic Commit Protocol
    • 2PC, 3PC, Paxos, Raft, ZAB