Blog
Mert Özen's blog posts on software development, backend, frontend, and DevOps.
Querying Application Insights and Log Analytics with KQL: where, summarize, bin, join, percentiles and Alert Queries
When you query Application Insights with KQL you count with sum(itemCount), not count(): with 25 percent sampling, 300 checkouts shrink to 82 rows and none of the 7 failed ones remains. We collect Bookstore's telemetry in the Application Insights schema without an Azure account and try where, summarize, percentile, bin, make-series, join, lookup, parse/extract and alert queries on real data.
Observability in Production: Azure Monitor and Application Insights, Sampling, Cost, PII and Auto-Instrumentation on Kubernetes
In production the cost and risk of telemetry are managed through sampling, volume and personal data: head sampling in the application on top of tail sampling loses most slow traces. With Bookstore we measure both settings, build a per-order budget of spans, logs and series, audit PII in Loki, and look at the new Microsoft OpenTelemetry Distro for Azure Monitor, semantic convention migrations and the Kubernetes Operator.