Compare Scenarios

Migration Step 1

Both scenarios define a migration step at this stage. Realtime Collaborative Editor: triggered by 'User-visible edit conflicts > 5% of sessions; poll interval '. Gaming Backend Platform: triggered by 'Single game server instance running at connection ceiling; h'.

Migration Step 2

Both scenarios define a migration step at this stage. Realtime Collaborative Editor: triggered by 'Data loss complaints from users editing simultaneously; conf'. Gaming Backend Platform: triggered by 'Game server instances blocking on PostgreSQL writes at end-o'.

Migration Step 3

Gaming Backend Platform has a defined migration; Realtime Collaborative Editor does not at this stage.

Server memory growing with active connections; file descriptor limits approached; new WebSocket connections refused

Tier 1: WebSocket Connection Ceiling: WebSocket server process connection limit or OS file descriptor ceiling. Recommended evolution: Increase file descriptor limits (ulimit); move to dedicated WebSocket server tier; implement connection multiplexing (multiple documents per connection where safe) .

Consecutive writes to the same document causing lock contention; write latency rising; auto-save batching queue depth increasing

Tier 2: Database Write Contention: High-frequency auto-save operations conflicting at the document row level; row-level locking under concurrent user edits . Recommended evolution: Move to operational transformation or CRDT-based conflict resolution; batch writes and resolve conflicts in-process before database commit; consider append-only event log for document operations .

Game server instance file descriptor count approaching OS limit (typically 65k open connections); WebSocket accept latency increasing; new connection establishment p99 > 200ms; CPU on game server instances > 70% during peak concurrent player count

Tier 1: WebSocket Connection Ceiling per Instance: Single game server instance WebSocket connection count limit; OS-level fd_max or application-level connection accept queue saturation. Recommended evolution: Increase OS fd_max to 512k and application connection accept queue depth; tune SO_REUSEPORT to allow multiple accept threads per socket; add game server instances and update consistent hashing ring; the affinity layer automatically routes new game rooms to the new instances as the ring expands: existing rooms are unaffected .

Redis command throughput > 500k/second; Redis CPU > 60%; per-tick Redis write latency p99 > 5ms (above the acceptable state sync threshold); game tick rate visibly dropping below target (30 ticks/second falling to 20) under load

Tier 2: Redis Game State Write Amplification: Game state serialization to Redis per tick producing more writes than expected; unoptimized state struct serialization writing entire state blob on any field change. Recommended evolution: Implement delta state serialization: only changed fields are written to Redis per tick using HSET with only the modified keys, not full state replacement; profile Redis command distribution per game tick to identify specific state fields with high churn; consider moving ephemeral per-tick state (player positions, projectile states) to local server memory with only durable state (scores, inventory changes) written to Redis .