03Prometheus memory jumped 400% overnight. Find the cause and stop it recurring.▼hard★ EssentialNewDatadogUberGrafana Labs2 repliesunlockedThe observability failure that scales with your success. Cardinality is the cost driver in every metrics system, and the fix has to be structural or it comes back next quarter.Open full answer →
05Counter, gauge, histogram, summary: which do you use for request latency, and why not the others?▼mediumNewDatadogGrafana LabsLinkedIn2 repliesunlockedA question with a right answer and a subtle reason. Histogram versus summary is the part that catches people, and it turns on whether you can aggregate across instances.Open full answer →
11Write the PromQL behind our availability SLO and tell me where these queries usually go wrong.▼hard★ EssentialNewUberRazorpayPhonePe○ sign inAnyone can divide bad requests by total. This answer shows the aggregation mistakes that quietly corrupt SLO dashboards, the rate-versus-increase traps that make budgets lie, and when subqueries cost too much.Open full answer →
