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Problem Understanding
Restate the problem in your own words.
Design a Distributed Logging System
Design a distributed logging system: thousands of microservices emit structured logs at high volume, the system collects, indexes, and stores them with a few seconds of ingest-to-query lag. Engineers run full-text searches over a 30-day retention with p99 < 5 s. The hard parts are the lossy-vs-lossless trade-off at volume (sampling, drop-on-overload), the index cost at billions of events/day, and tiered hot/warm/cold storage for retention economics.
- SplunkEnterprise logging + SIEM; the original heavy-weight in the space.
- Elastic Stack (ELK)Elasticsearch + Logstash + Kibana — open-source canonical answer.
- Datadog LogsHosted logs + APM — fast UX but expensive at scale; live tail + saved search are the demoware.
- Grafana LokiIndex-only-on-labels logging system — dramatically cheaper to operate; trades query flexibility for cost.
Your task: read the problem above, then write what the system is, who uses it, the rough scale, and the headline UX expectation — in your own words. Submit for AI review when you're ready.
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