Prometheus Monitoring System 3.15.0 / 2026-09-24
[CHANGE] PromQL: A range query whose end was not aligned to step caused subqueries inside it to evaluate past the parent's last actual step, inflating peakSamples in the query stats and against the query.max-samples limit, and wasting storage I/O reading samples that were never used in the result.
Executive Summary
[CHANGE] PromQL: A range query whose end was not aligned to step caused subqueries inside it to evaluate past the parent's last actual step, inflating peakSamples in the query stats and against the query.max-samples limit, and wasting storage I/O reading samples that were never used in the result. Add tests to prevent regression of the fix made in #18081 . #18598 [CHANGE] PromQL: Do not register a start timestamp reset if the start timestamp hasn't changed between subsequent samples.
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