Compare Scenarios

Migration Step 1

Both scenarios define a migration step at this stage. Distributed Job Queue Platform: triggered by 'Background jobs competing with user-facing API requests for '. IoT Telemetry Ingestion Platform: triggered by 'PostgreSQL write p99 > 100ms at sustained device fleet load;'.

Migration Step 2

Both scenarios define a migration step at this stage. Distributed Job Queue Platform: triggered by 'High-priority transactional jobs (e.g., payment processing, '. IoT Telemetry Ingestion Platform: triggered by 'Alerting system query latency > 500ms due to TimescaleDB que'.

Migration Step 3

Both scenarios define a migration step at this stage. Distributed Job Queue Platform: triggered by 'Multi-step jobs (e.g., ingest file → validate → transform → '. IoT Telemetry Ingestion Platform: triggered by 'Multi-device aggregate queries (fleet-wide max/min/avg over '.

Worker idle rate > 20% despite queue depth > 10k pending jobs; PostgreSQL pg_locks showing wait events on job table index; worker job claim p99 latency > 50ms (claim should be sub-10ms with correct indexing); CPU on PostgreSQL elevated from index scan overhead on job claim queries

Tier 1: Job Claim Lock Contention: Missing or misconfigured partial index on the job claim query; high worker concurrency driving SELECT FOR UPDATE SKIP LOCKED contention on a narrow hot page. Recommended evolution: Add a partial index on (priority DESC, created_at ASC) WHERE status = 'pending' AND run_at <= NOW(): the WHERE clause reduces the index to only claimable jobs, dramatically reducing index scan range; if contention persists, implement a job dispatch service (single dispatcher process) that batches claim queries and distributes job IDs to workers via an in-memory channel, removing per-worker database claims; tune FILLFACTOR on the job table to 70% to reduce hot page contention on SKIP LOCKED .

High-priority job queue depth growing despite workers available; low-priority batch jobs showing high throughput while transactional job latency (time from enqueue to execution start) p95 > 30s; worker pool metrics showing workers claiming jobs uniformly across priority levels rather than draining the high- priority queue first

Tier 2: Priority Inversion Under Load: Single worker pool consuming from all priority queues with equal weight; no priority-weighted polling implementation. Recommended evolution: Separate worker pools per priority tier (e.g., dedicated transactional workers for high-priority jobs, shared workers for low-priority batch); or implement priority-weighted polling in a unified worker pool (poll high-priority queue N times before polling low-priority queue once, where N is the priority weight ratio); add high-priority job execution latency as a first-class SLA metric with alerting threshold separate from batch job latency .

TimescaleDB write latency p99 > 50ms for batch INSERT operations; pg_stat_activity showing wait events on WAL flush; TimescaleDB active chunk autovacuum running continuously; Kafka consumer group lag for storage writers growing steadily at baseline (non-storm) load

Tier 1: TimescaleDB Write Throughput Ceiling: TimescaleDB single-node write throughput ceiling (~50k–100k rows/second depending on row width and chunk size configuration). Recommended evolution: Tune TimescaleDB chunk_time_interval to match write cadence (smaller chunks = faster compression, lower WAL amplification per chunk); enable native compression on chunks older than 1 hour to reduce on-disk footprint; add a dedicated NVMe volume for WAL separate from data directory; consider TimescaleDB multi-node for horizontal write distribution across data nodes .

Kafka consumer group lag jumping from baseline (<100k) to >10M messages within minutes; Kafka broker disk write rate elevated; TimescaleDB write thread pool fully saturated; Redis last-known-value update latency acceptable but historical storage significantly behind real-time; device reconnect event visible in device authentication logs correlating with lag spike

Tier 2: Kafka Consumer Lag from Reconnect Storm: Kafka consumer pool sized for steady-state throughput, not burst from device reconnect storm; insufficient storage writer parallelism for burst absorption. Recommended evolution: Pre-scale storage writer consumer replicas before anticipated high-risk windows (maintenance events, regional failovers); implement burst-aware consumer scaling using consumer group lag as the autoscale signal; tune Kafka consumer max.poll.records to batch storage INSERTs into TimescaleDB for higher per-consumer throughput (target 500–1000 rows per INSERT batch rather than single-row inserts) .