HyperLogLog: Count Distinct at Scale in 12KB
Counting unique items exactly costs memory that grows with your data. HyperLogLog estimates the cardinality of billions in about 12KB. Here's how it works.
#Observability(10)
Correlation IDs in FastAPI Logs
One async request scatters a dozen log lines through concurrent traffic. Thread a correlation ID through FastAPI with contextvars and trace it in OpenSearch.
OpenSearch ISM: Automate Index Rollover
Log indexes grow until a data node runs out of disk. How OpenSearch ISM rolls indexes over by size, ages them through hot and warm, then deletes on schedule.
Tracing a RAG Pipeline with OpenTelemetry
Trace a RAG pipeline with OpenTelemetry: instrument FastAPI, put each retrieval and model step in its own span, and read the latency waterfall in OpenSearch.
Zero-Downtime Reindexing in OpenSearch
Change an OpenSearch mapping without dropping writes or serving stale data. A step-by-step reindex with aliases, the Reindex API, and the failure modes.
Tracing an LLM Agent with OpenTelemetry
An LLM agent request hides where the time and tokens went behind one flat log. Trace it with OpenTelemetry spans, the GenAI conventions, and where it breaks.
Kubernetes OOMKilled: Requests vs Limits
Your pod died with OOMKilled and exit 137. What Kubernetes memory requests and limits actually do, what triggers the kill, and how to stop it happening.
Kubernetes Probes: Liveness, Readiness, Startup
Kubernetes has three health probes and mixing them up causes outages. How liveness, readiness, and startup probes work, and the failure modes to avoid.
ArgoCD Sync Waves: Ordering a Kubernetes Rollout
ArgoCD applies your whole app at once, so a migration races the pods that need it. How sync waves and hooks order a Kubernetes rollout, and where they stall.
OpenSearch Dashboards for Workflow Monitoring
Build an OpenSearch dashboard that watches a job pipeline: structured logs, an index mapping, the queries behind each panel, and alerts that fire early.