Overview

Redis cache for board state, task positions, and real-time WebSocket connections supporting collaborative board editing.

Caching Strategy

Board State

• Task Positions: Current task order in columns
• Active Filters: Per-user active filters
• Board Presence: Who’s viewing each board
• Optimistic Locks: Prevent concurrent edit conflicts

Real-time Data

• WebSocket Sessions: Active connections per board
• Presence Heartbeats: User activity timestamps
• Pending Updates: Queued board changes

Technical Details

Specifications:

• Version: Redis 7.x
• Memory: 16 GB
• Persistence: AOF enabled for durability
• Replication: Primary with 2 read replicas
• Pub/Sub: Enabled for WebSocket scaling

Performance:

• Latency: P99 < 2ms
• Throughput: 50,000 ops/second
• Pub/Sub Latency: < 10ms
• Connections: Max 5,000

Data Structures

Board State

board:{board_id}:state -> Board state (hash)
  - column_1: [task_1, task_3, task_5]
  - column_2: [task_2, task_4]
TTL: 1 hour

Presence

board:{board_id}:presence -> Active users (sorted set)
Score: Last heartbeat timestamp
TTL: 5 minutes

WebSocket Pub/Sub

Channel: board:{board_id}:updates
Messages: Board update events

Monitoring

• Memory Usage: Alert at 80%
• Pub/Sub Lag: Monitor message latency
• Connection Count: Track WebSocket connections
• Presence TTL: Monitor stale presence data