Kafka Monitoring: Alert on Lag Time, Not Message Count
The alert says lag = 50,000. At noon that is 5 seconds; at night it is 40 minutes. The fix: Alert on time, not record count.
In this chapter
Alert on how old the work is
What breaks
The alert says lag = 50,000. At noon that is 5 seconds; at night it is 40 minutes.
Three ways to respond
- One record-lag number for all: Records are not time.
- Alert on age, then check rates and health: Matches what users feel. (the fix)
- Autoscale on CPU: The bottleneck may not be CPU.
The fix: Alert on age, then check rates and health
Users feel freshness. Alert on event age, then use lag, throughput and broker health to find out why.
Remember: Alert on time, not record count.
More on Operations problems
- Kafka Simulator: Producers, Partitions and Consumer Groups
- How Uber, Netflix and Zomato Use Kafka: Real Architectures
- Kafka Interview Questions: 26 Real Production Problems
- Kafka vs a Message Queue: Why Events Stay After Reading
- Kafka Topics vs Partitions and Message Keys Explained
- Kafka Producer Batching: Async Send, linger.ms, batch.size
- Event-Driven Architecture with Kafka: Drop Sync Calls
- Kafka Fan-Out: One Event, Many Consumer Groups
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