Distributed Locking System - System Architecture
High-Level Architecture Overview
System Architecture Principles
Consensus-Based : Raft/Paxos for state replicationLeader-Based Writes : Single leader for all writesQuorum Reads : Majority reads for consistencySession-Based : Client sessions with heartbeatsWatch-Based Notifications : Event-driven updatesFault Tolerant : Survive minority node failures
Core Architecture Components
Copy ┌─────────────────────────────────────────────────────────────┐
│ Client Applications │
│ (Microservices, Distributed Systems, Databases) │
└─────────────────┬───────────────────────────────────────────┘
│
┌─────────┴─────────┬─────────────┬─────────────┐
│ │ │ │
┌───────▼────────┐ ┌───────▼────────┐ ┌───────▼────────┐
│ Lock Client │ │ Lock Client │ │ Lock Client │
│ Library │ │ Library │ │ Library │
└───────┬────────┘ └───────┬────────┘ └───────┬────────┘
│ │ │
└─────────┬─────────┴─────────────┘
│
┌─────────▼─────────┐
│ Load Balancer │
│ (Client-Side) │
└─────────┬─────────┘
│
┌─────────────┼─────────────┬─────────────┐
│ │ │ │
┌───▼────┐ ┌────▼───┐ ┌─────▼──┐ ┌───────▼────┐
│ Leader │ │Follower│ │Follower│ │ Follower │
│ Node 1 │ │ Node 2 │ │ Node 3 │ │ Node N │
└───┬────┘ └────┬───┘ └────┬───┘ └──────┬─────┘
│ │ │ │
└────────────┴───────────┴─────────────┘
│
┌────────▼────────┐
│ Raft Consensus │
│ Log Replication│
└────────┬────────┘
│
┌────────▼────────┐
│ Persistent Store│
│ (RocksDB/LevelDB)│
└─────────────────┘Raft Consensus Algorithm
Raft Overview
Copy Raft Components:
1. Leader Election
2. Log Replication
3. Safety Guarantees
Node States:
- Leader: Handles all writes, replicates to followers
- Follower: Receives log entries, votes in elections
- Candidate: Requests votes during election
Terms:
- Monotonically increasing election term
- Each term has at most one leader
- Used to detect stale information