My Release Notes

by Tiny Tools

/prometheus/prometheus/v3.12.0
v3.12.0
3.12.0 / 2026-05-28
View on GitHubView PackagePublished: May 28, 2026

Release Notes

  • [SECURITY] Remote-write: Reject snappy-compressed requests whose declared decoded length exceeds the 32MB. Thanks to @hibrian827 for reporting it. #18642
  • [SECURITY] STACKIT SD: Fix secrets being exposed in plaintext via /-/config endpoint. Thanks to @August829 and @Phaxma for reporting. GHSA-39j6-789q-qxvh #18649
  • [CHANGE] TSDB/Agent: Adds Start Timestamp field to all WAL Histogram samples in memory; used st-storage flag is enabled. #18221
  • [FEATURE] API: Add /api/v1/status/self_metrics endpoint returning the current state of the Prometheus server's own metrics about itself as JSON. #18411
  • [FEATURE] Discovery: Add DigitalOcean Managed Databases service discovery #18287
  • [FEATURE] Prometheus: Add support for the aix/ppc64 compilation target #18321
  • [FEATURE] Discovery: Add Outscale VM service discovery (outscale_sd_configs) for discovering scrape targets from the Outscale Cloud API. #18139
  • [FEATURE] PromQL: Emit a warning when sort, sort_by_label or sort_by_label_desc is used within range (matrix) queries, as these functions do not have effect in that context. #18498
  • [FEATURE] PromQL: Add start(), end(), range(), and step() experimental functions #17877
  • [FEATURE] PromQL: Update resets() function to consider start timestamp resets. Hidden behind use-start-timestamps feature flag. #18627
  • [FEATURE] Prometheus: Promote auto-reload-config as stable #18620
  • [FEATURE] TSDB/Agent: Add CheckpointFromInMemorySeries option to agent.DB that enables checkpoint based on in-memory series. #17948
  • [FEATURE] UI: Add a web interface for deleting time series and cleaning tombstones, accessible from the Status menu. #18390
  • [FEATURE] PromQL: Use start timestamps for rate(), irate(), and increase()calculations, behind a feature flaguse-start-timestamps. Doesn't work together with extended range selectors anchoredandsmoothed`. #18344
  • [FEATURE] Scrape: Added a feature flag st-synthesis which synthesizes unknown STs for scraped cumulative metrics. Useful when Remote Writing 2.0 with delta or Otel-based backends. #18279
  • [FEATURE] promqltest: support @st annotation in load blocks to specify per-sample start timestamps. #18360
  • [ENHANCEMENT] API: reject concurrent fgprof profiles. #18651
  • [ENHANCEMENT] AWS SD: Add optional external_id field to ECS/MSK/RDS/Elasticache. #18579
  • [ENHANCEMENT] AWS SD: Add optional external_id field. #17171
  • [ENHANCEMENT] Discovery: Propagate SD target updates faster by introducing dynamic backoff interval instead of static 5s interval for throttling. #18187
  • [ENHANCEMENT] Promtool: Add --header flag to query instant command, matching existing query range behaviour. #18418
  • [ENHANCEMENT]: AWS SD: Allows EC2 service discovery to discover IPv6 addresses to communicate with target endpoints. The private IPv4 address remains the default when both IPv4 and IPv6 addresses are present. #16088
  • [PERF] TSDB: Make head chunk lookup in range queries constant time instead of quadratic time #18302
  • [PERF] TSDB: Skip entire stripes in mmapHeadChunks when no series need mmapping, reducing CPU utilization significantly at production-relevant scales. #18541
  • [PERF] TSDB: Skip clean series during periodic head chunk mmap using cached head chunk count #18272
  • [PERF] PromQL: Address FloatHistogram.KahanAdd performance regression on Go 1.26. #18568
  • [BUGFIX] PromQL: Fix info() function incorrectly handling negated __name__ matchers #17932
  • [BUGFIX] API: Return duration expressions in /parse_ast. #18624
  • [BUGFIX] API: correctly document formats accepted for duration query request parameters (step, timeout and lookback delta) in OpenAPI spec #18305
  • [BUGFIX] Scrape: AppenderV2 now tracks staleness even when OOO/duplicate series errors happen similar to AppenderV1 #18567
  • [BUGFIX] Config: Validate remote_write queue_config fields at load time to prevent runtime panic and silent misconfiguration. #18209
  • [BUGFIX] Discovery/Consul: Add health_filter for Health API filtering, fixing breakage when using Catalog-only fields like ServiceTags in filter. #18479 #18499
  • [BUGFIX] OTLP: limit decompressed body size for gzip-encoded OTLP write requests. #18408
  • [BUGFIX] PromQL: Fix smoothed rate/increase returning zero instead of no result when all data falls strictly after the query range. #18523
  • [BUGFIX] PromQL: Fix metric name not being dropped when last_over_time or first_over_time is applied to subqueries containing name-dropping functions like abs(). #18409
  • [BUGFIX] PromQL: Fix missing warning when mixing exponential and custom-bucket histograms in stats queries. #18660
  • [BUGFIX] PromQL: Fix parsing of range() keyword in duration expressions such as foo[5m+range()]. #18623
  • [BUGFIX] PromQL: Fix smoothed vector selector returning no results in binary operations when the @ modifier is used. #18531
  • [BUGFIX] PromQL: Reject NaN, infinite, and out-of-range duration expressions instead of silently producing an out-of-range time.Duration. #18639
  • [BUGFIX] Scrape: Fix panic when scraping malformed native histograms. #18414
  • [BUGFIX] Scrape: fix panic when scraping a target exposing a summary with no quantiles via the protobuf format. #18382
  • [BUGFIX] Scrape: fix scrape failure log file occasionally not applied after a configuration reload. #18421
  • [BUGFIX] TSDB: Allow retention percentage with new data path. #18628
  • [BUGFIX] TSDB: Preserve decimal precision in percentage-based retention #18374
  • [BUGFIX] TSDB: fix prometheus_tsdb_head_chunks going negative after WAL replay #18401
  • [BUGFIX] TSDB: panic with native histograms during query of overlapping chunks. #18692
  • [BUGFIX] Tracing: fix startup failure for insecure OTLP HTTP tracing #18469
  • [BUGFIX] UI: Escape label values offered by PromQL autocomplete. #18658
  • [BUGFIX] UI: Improve Y-axis tick label precision for graph values over small ranges. #18682
  • [BUGFIX] prometheus_sd_refresh* and prometheus_sd_discovered_targets metrics for specific scrape jobs are deleted when the scrape job is removed. #17614
  • [BUGFIX] Remote: fixed validation for received RW2 requests when parsing metadata unit symbols. This fixes a case when request would cause (recovered) handler panic. #18641
  • [BUGFIX] TSDB/Agent: fix race in agent appender where concurrent appends for the same label set could produce duplicate in-memory series and duplicate WAL records. #18292
  • [BUGFIX] Config: Update --enable-feature flag description and sort feature names. #18487