fix(model/histogram): do not miss counter resets behind empty buckets in DetectReset by sueun-dev · Pull Request #19367 · prometheus/prometheus

sueun-dev · 2026-08-08T08:52:56Z

FloatHistogram.DetectReset walks the previous histogram's buckets through the detectReset helper. Two of its inner loops advance the previous iterator with prevIt.Next() but never reassign prevBucket = prevIt.strippedAt(), so they keep inspecting the first previous bucket instead of moving on. One loop handles the case where the current histogram has no buckets at all; the other handles the current iterator running out before the previous one.

When the first previous bucket is empty and a later one is populated, and the current histogram no longer has that later bucket, the loops reach the end without ever seeing the populated bucket and return false, so a real counter reset is missed. The main loop further down already reassigns prevBucket after advancing; the integer DetectReset proposed in #18313 handles the same loops correctly, so these two float loops were the exception.

DetectReset drives counter-reset detection for native-histogram rate(), increase() and related functions (through promql/histogram_stats_iterator.go and promql/functions.go) and for scrape-time synthesis in scrape/st_synthesis.go, so a missed reset makes those results undercount.

I added two cases to the existing TestFloatHistogramDetectReset table, one for each loop. Both fail on current main and pass with this change.

[BUGFIX] Native histograms: `DetectReset` no longer misses a counter reset when a populated bucket behind an empty one disappears, which could make histogram `rate()`/`increase()` undercount.

… in DetectReset The two inner loops in the detectReset helper advance prevIt with prevIt.Next() but never reassign prevBucket = prevIt.strippedAt(), so they keep inspecting the first previous bucket. When that bucket is empty and a later one is populated and missing from the current histogram, DetectReset returns false and misses a real counter reset, which can make native-histogram rate()/increase() undercount. Added two cases to TestFloatHistogramDetectReset that fail before and pass after. Signed-off-by: Sueun Cho <[email protected]>

linasm

LGTM, thanks. AFAIK tests on Windows are flaky, hopefully one of maintainers will rerun it.

Native histograms with custom buckets (NHCB) may change their bucket layout from one sample to the next, for instance when an exporter only reports the latency ranges it observed. Histograms with different layouts cannot be added, so downsampling such a series panicked with "cannot apply this operation on custom buckets histograms with different custom bounds". Plan histogram output windows first: reduce the custom buckets histograms of each window to the layout they have in common (merging adjacent buckets at shared boundaries keeps count, sum, rate and increase exact and only coarsens quantile resolution inside that window), group consecutive windows with append-compatible layouts into segments, and emit every segment as its own aggregate chunk. The 5m to 1h path plans the counter, sum and count streams jointly so that every aggregate chunk holds aligned sub-chunks. A window mixing exponential and custom buckets cannot be aggregated and fails with an explicit error instead of being dropped. Two related defects surfaced while validating this on production data and are fixed here as well. The chunk builder now tells appender recodes from cuts: a cut used to replace the aggregate chunk, silently discarding every window already in it, and now fails the batch. The aggregator applies counter reset semantics whenever the delta between consecutive samples regresses, which covers resets the pinned Prometheus DetectReset misses (prometheus/prometheus#19367) and resets hidden behind a NotCounterReset hint; either case made the emitted cumulative counter regress and the appender cut. DownsampleRaw returns an error instead of panicking; pkg/dedup tests are adapted accordingly. Refs thanos-io#8698. Co-Authored-By: Claude Fable 5 <[email protected]> Claude-Session: https://claude.ai/code/session_01Kmx1xPQMBkULUVCjrsb6JH Signed-off-by: Victor Bogo <[email protected]>

##### [\`v3.15.0\`](https://github.com/prometheus/prometheus/releases/tag/v3.15.0) - \[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](prometheus/prometheus#18081). [#18598](prometheus/prometheus#18598) - \[CHANGE] PromQL: Do not register a start timestamp reset if the start timestamp hasn't changed between subsequent samples. [#19454](prometheus/prometheus#19454) - \[CHANGE] Logging: Deprecate `--log.level`; use `runtime.log_level` configuration to supply the default level. [#19511](prometheus/prometheus#19511) - \[FEATURE] Configuration: Allow changing the process log level through `runtime.log_level` on configuration reload. [#19511](prometheus/prometheus#19511) - \[FEATURE] Prometheus: Add `--auto-gomemlimit.refresh-interval` flag to periodically re-detect the container or system memory limit and update `GOMEMLIMIT` at runtime. [#18843](prometheus/prometheus#18843) - \[FEATURE] Scraping: Add support for scraping targets via Unix Domain Sockets. [#12024](prometheus/prometheus#12024). [#18091](prometheus/prometheus#18091) - \[FEATURE] scrape: Implement OM2.0 scrape format. [#18606](prometheus/prometheus#18606) - \[ENHANCEMENT] Reduce TSDB head CPU utilization when initializing. [#18001](prometheus/prometheus#18001) - \[ENHANCEMENT] Docker SD: Add labels `__meta_docker_container_image` and `__meta_docker_container_image_id`. [#19386](prometheus/prometheus#19386) - \[ENHANCEMENT] Mixin: Add a p95/p99 remote-write send-batch latency panel to the remote-write dashboard. [#19500](prometheus/prometheus#19500) - \[ENHANCEMENT] Mixin: Support native histograms in the remote-write send-batch latency panel. [#19522](prometheus/prometheus#19522) - \[ENHANCEMENT] PromQL/TSDB: The `--enable-feature=st-storage` flag now automatically enables XOR2 float chunk encoding and ST-capable histogram chunk encoding, so you no longer need to pass `xor2-encoding` and `histograms-st-encoding` alongside it. [#19518](prometheus/prometheus#19518) - \[ENHANCEMENT] Remote write / Alertmanager: upgrade sigv4 to v0.5.0, adding `session_name` and `tags` fields for STS AssumeRole sessions. The previously undocumented `service_name` field is now also documented. [#19569](prometheus/prometheus#19569) - \[ENHANCEMENT] Scraping: Support zstd-compressed scrape responses, enabled via feature flag `zstd-scrape`. [#19502](prometheus/prometheus#19502) - \[ENHANCEMENT] TSDB: Stabilize the XOR2 float chunk encoding. `--enable-feature=xor2-encoding` is deprecated; use `storage.tsdb.chunk_encoding.floats: xor2` instead. Check that other software reading the TSDB directly (e.g. Thanos sidecar) supports XOR2 before enabling. [#19461](prometheus/prometheus#19461) - \[ENHANCEMENT] TSDB: add `prometheus_tsdb_head_appenders_created_total` metric. [#19411](prometheus/prometheus#19411) - \[ENHANCEMENT] Tracing: add more spans to scrapes, API queries and rule evaluations. [#19410](prometheus/prometheus#19410) - \[ENHANCEMENT] UI: Show the effective configuration for each scrape pool on the Targets and Service Discovery pages. [#19384](prometheus/prometheus#19384) - \[ENHANCEMENT] scrape: Enable start time synthesis for summary `_count` and `_sum` series in scrape appender v2. [#19323](prometheus/prometheus#19323) - \[ENHANCEMENT] scrape: stop all pools in parallel for faster shutdowns. [#19295](prometheus/prometheus#19295) - \[ENHANCEMENT] storage/remote: Add undocumented failed\_request\_logging config field to debug log remote write V2 requests on send errors. [#19249](prometheus/prometheus#19249) - \[ENHANCEMENT] TSDB: Add fast path for XOR chunk decompression to speed up queries. [#18049](prometheus/prometheus#18049) - \[ENHANCEMENT] UI: Improve native histogram table formatting and add a background bar indicating the bucket count. [#19332](prometheus/prometheus#19332) - \[ENHANCEMENT] TSDB: Add `prometheus_tsdb_head_series_pending_commit_underflow_total` to report pending-sample reservation underflows. [#19470](prometheus/prometheus#19470) - \[PERF] AWS SD: Build RDS cluster labels once per cluster instead of once per instance. [#19504](prometheus/prometheus#19504) - \[PERF] AWS SD: Describe RDS instances of different clusters concurrently, bounded by `request_concurrency`. [#19506](prometheus/prometheus#19506) - \[PERF] AWS SD: Describe each ElastiCache resource once per refresh instead of twice. [#19585](prometheus/prometheus#19585) - \[PERF] Remote read: Avoid cloning labels for sampled reads when no external labels are configured. [#19503](prometheus/prometheus#19503) - \[PERF] Remote write: Reuse OTLP converter scratch state between requests. [#19388](prometheus/prometheus#19388) - \[PERF] scrape: conversion from classic to native histograms should only parse start times when enabled. [#19446](prometheus/prometheus#19446) - \[BUGFIX] PromQL: Fix `info()` enrichment for composite expressions with mixed `@`/offset references or selector-free vector branches, preventing metadata from being evaluated at an unrelated timestamp. [#19387](prometheus/prometheus#19387) - \[BUGFIX] PromQL: Fix info() enrichment when input series use different subsets of identifying labels. [#19557](prometheus/prometheus#19557) - \[BUGFIX] PromQL: Preserve metric-name dropping through the info function when delayed name removal is enabled. [#19413](prometheus/prometheus#19413) - \[BUGFIX] TSDB: Don't silently drop samples when head garbage collection removes a series while it is being appended to. [#19272](prometheus/prometheus#19272) - \[BUGFIX] TSDB: Keep series with uncommitted samples during selected- and stale-series compaction, including when appenders overlap. [#19470](prometheus/prometheus#19470) - \[BUGFIX] TSDB: Do not retain head series after a synthetic start-timestamp zero sample is rejected. [#19470](prometheus/prometheus#19470) - \[BUGFIX] TSDB: Prevent query panics during series eviction after WAL replay. [#19664](prometheus/prometheus#19664) - \[BUGFIX] TSDB: fix potential deadlock between mmapSeriesChunks and gcSeries. [#19460](prometheus/prometheus#19460) - \[BUGFIX] TSDB: fix default block reload interval for custom options. [#19368](prometheus/prometheus#19368) - \[BUGFIX] AWS SD: Do not crash on serverless MSK clusters or MSK clusters without Open Monitoring. [#19194](prometheus/prometheus#19194) - \[BUGFIX] AWS SD: Do not panic when the ElastiCache API omits optional fields of a serverless cache or cache cluster. [#19435](prometheus/prometheus#19435) - \[BUGFIX] AWS SD: Reject non-positive `request_concurrency` instead of hanging service discovery indefinitely. [#19524](prometheus/prometheus#19524) - \[BUGFIX] Discovery/AWS: Avoid a panic when discovering standalone ECS tasks with custom task groups. [#19302](prometheus/prometheus#19302) - \[BUGFIX] Discovery: Do not panic in AWS Lightsail service discovery when an instance is missing optional fields such as availability zone, blueprint, bundle, name, state or support code. [#19324](prometheus/prometheus#19324) - \[BUGFIX] Discovery: delete the stale `prometheus_sd_last_update_timestamp_seconds` series for a config that is removed on reload. [#19131](prometheus/prometheus#19131) - \[BUGFIX] HTTP: Avoid truncating compressed responses when handlers set Content-Length. [#19661](prometheus/prometheus#19661) - \[BUGFIX] IONOS SD: Do not panic when the API response omits the server, NIC or volume collections, or a server's properties. [#19438](prometheus/prometheus#19438) - \[BUGFIX] Metadata will not affect the number of Remote Write v2 shards. [#19218](prometheus/prometheus#19218) - \[BUGFIX] Mixins: Fix label mismatches that prevented PrometheusHAGroupNotIngestingSamples and PrometheusHAGroupCrashlooping from firing. [#19444](prometheus/prometheus#19444) - \[BUGFIX] Native histograms: `DetectReset` no longer misses a counter reset when a populated bucket behind an empty one disappears, which could make histogram `rate()`/`increase()` undercount. [#19367](prometheus/prometheus#19367) - \[BUGFIX] Never skip histogram buckets for histogram\_stddev and histogram\_stdvar functions. [#19521](prometheus/prometheus#19521) - \[BUGFIX] OTLP: Do not abort an entire OTLP payload ingestion if one metric has no datapoints. [#19343](prometheus/prometheus#19343) - \[BUGFIX] PromQL: Fix FastRegexMatcher false-positive match when a capturing group is directly adjacent to a literal (e.g. `.*\|(foo)\|.*`). [#19516](prometheus/prometheus#19516) - \[BUGFIX] PromQL: Fix a panic in range selectors using the experimental `anchored` or `smoothed` modifier when the selected series has no samples inside the query window, for example a query evaluated inside a scrape gap. [#19431](prometheus/prometheus#19431) - \[BUGFIX] PromQL: Fix empty results when a subquery with `@` is used as the matrix argument of a call that is not step-invariant (for example `quantile_over_time(scalar(x), metric[...:...] @ T)`). [#19187](prometheus/prometheus#19187) - \[BUGFIX] PromQL: Make the "found duplicate series for the match group" many-to-many matching error message deterministic by sorting the two duplicate labels. [#18810](prometheus/prometheus#18810) - \[BUGFIX] PromQL: Preserve parentheses around duration literals on Expr.String() round-trip. [#19403](prometheus/prometheus#19403) - \[BUGFIX] PromQL: Reject duration-expression offsets and `@ start()` / `@ end()` before range selectors, matching the existing rejection of literal offsets and `@ <timestamp>`. [#19406](prometheus/prometheus#19406) - \[BUGFIX] PromQL: Report the position of the histogram argument rather than of a scalar argument in the native histogram NaN observation annotations of `histogram_quantile` and `histogram_fraction`. [#19330](prometheus/prometheus#19330) - \[BUGFIX] PromQL: info() now applies the @ modifier/offset when evaluating the info series, so info(v @ T) enriches as of T consistently instead of depending on the query start/eval time. [#19266](prometheus/prometheus#19266) - \[BUGFIX] Rules: Fix a panic when a rule manager created without a logger loads a rule file containing multiple YAML documents. [#19433](prometheus/prometheus#19433) - \[BUGFIX] Scrape: Do not append a stale marker for a series that is still exposed when the storage returns a new series reference for it. [#19328](prometheus/prometheus#19328) - \[BUGFIX] Scrape: JSON log formatter correctly format scrape target info. [#19472](prometheus/prometheus#19472) - \[BUGFIX] TSDB: Fix in-order chunk ID overflow by wrapping head chunk IDs modulo 2^23 so they never collide with the out-of-order flag bit. [#19450](prometheus/prometheus#19450) - \[BUGFIX] TSDB: Fix out-of-order chunk ID overflow by wrapping `firstOOOChunkID` modulo 2^23 instead of growing unbounded. [#19216](prometheus/prometheus#19216) - \[BUGFIX] UI: Remove an extraneous X-axis tick mark in the native histogram chart when using the "linear" display mode. [#19326](prometheus/prometheus#19326) - \[BUGFIX] discovery/aws: Avoid a panic when an ElastiCache ARN is missing its resource ID. [#19333](prometheus/prometheus#19333) - \[BUGFIX] discovery/aws: Do not panic on MSK clusters whose optional API fields are absent. [#19584](prometheus/prometheus#19584) - \[BUGFIX] discovery/aws: Do not panic when the EC2 API omits optional instance fields. [#19512](prometheus/prometheus#19512) - \[BUGFIX] discovery/aws: Don't panic on ECS tasks with absent optional fields. [#19396](prometheus/prometheus#19396) - \[BUGFIX] discovery/aws: MSK Optional Custom Configuration Fields [#19422](prometheus/prometheus#19422). [#19422](prometheus/prometheus#19422) - \[BUGFIX] discovery/ionos: Fix panic when the IONOS API omits optional server fields. [#19418](prometheus/prometheus#19418) - \[BUGFIX] discovery/kubernetes: Populate `__meta_kubernetes_service_loadbalancer_ip` from `status.loadBalancer.ingress`, falling back to deprecated `spec.loadBalancerIP`. [#19404](prometheus/prometheus#19404) - \[BUGFIX] histogram: Fix Compact moving buckets to wrong indices, and producing negative bucket counts for integer histograms, when more than one span is merged in the same pass. [#19312](prometheus/prometheus#19312) - \[BUGFIX] promtool: Fixed `tsdb dump` silently dropping native histogram samples. [#18051](prometheus/prometheus#18051) - \[BUGFIX] scrape: fix data race in `Manager.TargetsDroppedCounts` to avoid miscounting dropped targets. [#19304](prometheus/prometheus#19304) - \[BUGFIX] scrape: fix nil histogram when native and classic histograms are mixed in one metric family. [#19452](prometheus/prometheus#19452) - \[BUGFIX] TSDB: Fix WAL and GC log messages to emit human-readable duration strings instead of nanosecond integers. [#19307](prometheus/prometheus#19307) - \[BUGFIX] TSDB: Avoid WAL corruption after a failed WAL write in Agent mode. [#19700](prometheus/prometheus#19700) - \[BUGFIX] Agent: Ignore unknown WAL record types, to help users rolling back. [#19814](prometheus/prometheus#19814)

…→ v3.15.0) (#769) This PR contains the following updates: | Package | Update | Change | |---|---|---| | [quay.io/prometheus/prometheus](https://github.com/prometheus/prometheus) | minor | `v3.14.0` → `v3.15.0` | --- ### Release Notes <details> <summary>prometheus/prometheus (quay.io/prometheus/prometheus)</summary> ### [`v3.15.0`](https://github.com/prometheus/prometheus/releases/tag/v3.15.0): 3.15.0 / 2026-09-24 [Compare Source](prometheus/prometheus@v3.14.0...v3.15.0) - \[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](prometheus/prometheus#18081). [#18598](prometheus/prometheus#18598) - \[CHANGE] PromQL: Do not register a start timestamp reset if the start timestamp hasn't changed between subsequent samples. [#19454](prometheus/prometheus#19454) - \[CHANGE] Logging: Deprecate `--log.level`; use `runtime.log_level` configuration to supply the default level. [#19511](prometheus/prometheus#19511) - \[FEATURE] Configuration: Allow changing the process log level through `runtime.log_level` on configuration reload. [#19511](prometheus/prometheus#19511) - \[FEATURE] Prometheus: Add `--auto-gomemlimit.refresh-interval` flag to periodically re-detect the container or system memory limit and update `GOMEMLIMIT` at runtime. [#18843](prometheus/prometheus#18843) - \[FEATURE] Scraping: Add support for scraping targets via Unix Domain Sockets. [#12024](prometheus/prometheus#12024). [#18091](prometheus/prometheus#18091) - \[FEATURE] scrape: Implement OM2.0 scrape format. [#18606](prometheus/prometheus#18606) - \[ENHANCEMENT] Reduce TSDB head CPU utilization when initializing. [#18001](prometheus/prometheus#18001) - \[ENHANCEMENT] Docker SD: Add labels `__meta_docker_container_image` and `__meta_docker_container_image_id`. [#19386](prometheus/prometheus#19386) - \[ENHANCEMENT] Mixin: Add a p95/p99 remote-write send-batch latency panel to the remote-write dashboard. [#19500](prometheus/prometheus#19500) - \[ENHANCEMENT] Mixin: Support native histograms in the remote-write send-batch latency panel. [#19522](prometheus/prometheus#19522) - \[ENHANCEMENT] PromQL/TSDB: The `--enable-feature=st-storage` flag now automatically enables XOR2 float chunk encoding and ST-capable histogram chunk encoding, so you no longer need to pass `xor2-encoding` and `histograms-st-encoding` alongside it. [#19518](prometheus/prometheus#19518) - \[ENHANCEMENT] Remote write / Alertmanager: upgrade sigv4 to v0.5.0, adding `session_name` and `tags` fields for STS AssumeRole sessions. The previously undocumented `service_name` field is now also documented. [#19569](prometheus/prometheus#19569) - \[ENHANCEMENT] Scraping: Support zstd-compressed scrape responses, enabled via feature flag `zstd-scrape`. [#19502](prometheus/prometheus#19502) - \[ENHANCEMENT] TSDB: Stabilize the XOR2 float chunk encoding. `--enable-feature=xor2-encoding` is deprecated; use `storage.tsdb.chunk_encoding.floats: xor2` instead. Check that other software reading the TSDB directly (e.g. Thanos sidecar) supports XOR2 before enabling. [#19461](prometheus/prometheus#19461) - \[ENHANCEMENT] TSDB: add `prometheus_tsdb_head_appenders_created_total` metric. [#19411](prometheus/prometheus#19411) - \[ENHANCEMENT] Tracing: add more spans to scrapes, API queries and rule evaluations. [#19410](prometheus/prometheus#19410) - \[ENHANCEMENT] UI: Show the effective configuration for each scrape pool on the Targets and Service Discovery pages. [#19384](prometheus/prometheus#19384) - \[ENHANCEMENT] scrape: Enable start time synthesis for summary `_count` and `_sum` series in scrape appender v2. [#19323](prometheus/prometheus#19323) - \[ENHANCEMENT] scrape: stop all pools in parallel for faster shutdowns. [#19295](prometheus/prometheus#19295) - \[ENHANCEMENT] storage/remote: Add undocumented failed\_request\_logging config field to debug log remote write V2 requests on send errors. [#19249](prometheus/prometheus#19249) - \[ENHANCEMENT] TSDB: Add fast path for XOR chunk decompression to speed up queries. [#18049](prometheus/prometheus#18049) - \[ENHANCEMENT] UI: Improve native histogram table formatting and add a background bar indicating the bucket count. [#19332](prometheus/prometheus#19332) - \[ENHANCEMENT] TSDB: Add `prometheus_tsdb_head_series_pending_commit_underflow_total` to report pending-sample reservation underflows. [#19470](prometheus/prometheus#19470) - \[PERF] AWS SD: Build RDS cluster labels once per cluster instead of once per instance. [#19504](prometheus/prometheus#19504) - \[PERF] AWS SD: Describe RDS instances of different clusters concurrently, bounded by `request_concurrency`. [#19506](prometheus/prometheus#19506) - \[PERF] AWS SD: Describe each ElastiCache resource once per refresh instead of twice. [#19585](prometheus/prometheus#19585) - \[PERF] Remote read: Avoid cloning labels for sampled reads when no external labels are configured. [#19503](prometheus/prometheus#19503) - \[PERF] Remote write: Reuse OTLP converter scratch state between requests. [#19388](prometheus/prometheus#19388) - \[PERF] scrape: conversion from classic to native histograms should only parse start times when enabled. [#19446](prometheus/prometheus#19446) - \[BUGFIX] PromQL: Fix `info()` enrichment for composite expressions with mixed `@`/offset references or selector-free vector branches, preventing metadata from being evaluated at an unrelated timestamp. [#19387](prometheus/prometheus#19387) - \[BUGFIX] PromQL: Fix info() enrichment when input series use different subsets of identifying labels. [#19557](prometheus/prometheus#19557) - \[BUGFIX] PromQL: Preserve metric-name dropping through the info function when delayed name removal is enabled. [#19413](prometheus/prometheus#19413) - \[BUGFIX] TSDB: Don't silently drop samples when head garbage collection removes a series while it is being appended to. [#19272](prometheus/prometheus#19272) - \[BUGFIX] TSDB: Keep series with uncommitted samples during selected- and stale-series compaction, including when appenders overlap. [#19470](prometheus/prometheus#19470) - \[BUGFIX] TSDB: Do not retain head series after a synthetic start-timestamp zero sample is rejected. [#19470](prometheus/prometheus#19470) - \[BUGFIX] TSDB: Prevent query panics during series eviction after WAL replay. [#19664](prometheus/prometheus#19664) - \[BUGFIX] TSDB: fix potential deadlock between mmapSeriesChunks and gcSeries. [#19460](prometheus/prometheus#19460) - \[BUGFIX] TSDB: fix default block reload interval for custom options. [#19368](prometheus/prometheus#19368) - \[BUGFIX] AWS SD: Do not crash on serverless MSK clusters or MSK clusters without Open Monitoring. [#19194](prometheus/prometheus#19194) - \[BUGFIX] AWS SD: Do not panic when the ElastiCache API omits optional fields of a serverless cache or cache cluster. [#19435](prometheus/prometheus#19435) - \[BUGFIX] AWS SD: Reject non-positive `request_concurrency` instead of hanging service discovery indefinitely. [#19524](prometheus/prometheus#19524) - \[BUGFIX] Discovery/AWS: Avoid a panic when discovering standalone ECS tasks with custom task groups. [#19302](prometheus/prometheus#19302) - \[BUGFIX] Discovery: Do not panic in AWS Lightsail service discovery when an instance is missing optional fields such as availability zone, blueprint, bundle, name, state or support code. [#19324](prometheus/prometheus#19324) - \[BUGFIX] Discovery: delete the stale `prometheus_sd_last_update_timestamp_seconds` series for a config that is removed on reload. [#19131](prometheus/prometheus#19131) - \[BUGFIX] HTTP: Avoid truncating compressed responses when handlers set Content-Length. [#19661](prometheus/prometheus#19661) - \[BUGFIX] IONOS SD: Do not panic when the API response omits the server, NIC or volume collections, or a server's properties. [#19438](prometheus/prometheus#19438) - \[BUGFIX] Metadata will not affect the number of Remote Write v2 shards. [#19218](prometheus/prometheus#19218) - \[BUGFIX] Mixins: Fix label mismatches that prevented PrometheusHAGroupNotIngestingSamples and PrometheusHAGroupCrashlooping from firing. [#19444](prometheus/prometheus#19444) - \[BUGFIX] Native histograms: `DetectReset` no longer misses a counter reset when a populated bucket behind an empty one disappears, which could make histogram `rate()`/`increase()` undercount. [#19367](prometheus/prometheus#19367) - \[BUGFIX] Never skip histogram buckets for histogram\_stddev and histogram\_stdvar functions. [#19521](prometheus/prometheus#19521) - \[BUGFIX] OTLP: Do not abort an entire OTLP payload ingestion if one metric has no datapoints. [#19343](prometheus/prometheus#19343) - \[BUGFIX] PromQL: Fix FastRegexMatcher false-positive match when a capturing group is directly adjacent to a literal (e.g. `.*\|(foo)\|.*`). [#19516](prometheus/prometheus#19516) - \[BUGFIX] PromQL: Fix a panic in range selectors using the experimental `anchored` or `smoothed` modifier when the selected series has no samples inside the query window, for example a query evaluated inside a scrape gap. [#19431](prometheus/prometheus#19431) - \[BUGFIX] PromQL: Fix empty results when a subquery with `@` is used as the matrix argument of a call that is not step-invariant (for example `quantile_over_time(scalar(x), metric[...:...] @ T)`). [#19187](prometheus/prometheus#19187) - \[BUGFIX] PromQL: Make the "found duplicate series for the match group" many-to-many matching error message deterministic by sorting the two duplicate labels. [#18810](prometheus/prometheus#18810) - \[BUGFIX] PromQL: Preserve parentheses around duration literals on Expr.String() round-trip. [#19403](prometheus/prometheus#19403) - \[BUGFIX] PromQL: Reject duration-expression offsets and `@ start()` / `@ end()` before range selectors, matching the existing rejection of literal offsets and `@ <timestamp>`. [#19406](prometheus/prometheus#19406) - \[BUGFIX] PromQL: Report the position of the histogram argument rather than of a scalar argument in the native histogram NaN observation annotations of `histogram_quantile` and `histogram_fraction`. [#19330](prometheus/prometheus#19330) - \[BUGFIX] PromQL: info() now applies the @ modifier/offset when evaluating the info series, so info(v @ T) enriches as of T consistently instead of depending on the query start/eval time. [#19266](prometheus/prometheus#19266) - \[BUGFIX] Rules: Fix a panic when a rule manager created without a logger loads a rule file containing multiple YAML documents. [#19433](prometheus/prometheus#19433) - \[BUGFIX] Scrape: Do not append a stale marker for a series that is still exposed when the storage returns a new series reference for it. [#19328](prometheus/prometheus#19328) - \[BUGFIX] Scrape: JSON log formatter correctly format scrape target info. [#19472](prometheus/prometheus#19472) - \[BUGFIX] TSDB: Fix in-order chunk ID overflow by wrapping head chunk IDs modulo 2^23 so they never collide with the out-of-order flag bit. [#19450](prometheus/prometheus#19450) - \[BUGFIX] TSDB: Fix out-of-order chunk ID overflow by wrapping `firstOOOChunkID` modulo 2^23 instead of growing unbounded. [#19216](prometheus/prometheus#19216) - \[BUGFIX] UI: Remove an extraneous X-axis tick mark in the native histogram chart when using the "linear" display mode. [#19326](prometheus/prometheus#19326) - \[BUGFIX] discovery/aws: Avoid a panic when an ElastiCache ARN is missing its resource ID. [#19333](prometheus/prometheus#19333) - \[BUGFIX] discovery/aws: Do not panic on MSK clusters whose optional API fields are absent. [#19584](prometheus/prometheus#19584) - \[BUGFIX] discovery/aws: Do not panic when the EC2 API omits optional instance fields. [#19512](prometheus/prometheus#19512) - \[BUGFIX] discovery/aws: Don't panic on ECS tasks with absent optional fields. [#19396](prometheus/prometheus#19396) - \[BUGFIX] discovery/aws: MSK Optional Custom Configuration Fields [#19422](prometheus/prometheus#19422). [#19422](prometheus/prometheus#19422) - \[BUGFIX] discovery/ionos: Fix panic when the IONOS API omits optional server fields. [#19418](prometheus/prometheus#19418) - \[BUGFIX] discovery/kubernetes: Populate `__meta_kubernetes_service_loadbalancer_ip` from `status.loadBalancer.ingress`, falling back to deprecated `spec.loadBalancerIP`. [#19404](prometheus/prometheus#19404) - \[BUGFIX] histogram: Fix Compact moving buckets to wrong indices, and producing negative bucket counts for integer histograms, when more than one span is merged in the same pass. [#19312](prometheus/prometheus#19312) - \[BUGFIX] promtool: Fixed `tsdb dump` silently dropping native histogram samples. [#18051](prometheus/prometheus#18051) - \[BUGFIX] scrape: fix data race in `Manager.TargetsDroppedCounts` to avoid miscounting dropped targets. [#19304](prometheus/prometheus#19304) - \[BUGFIX] scrape: fix nil histogram when native and classic histograms are mixed in one metric family. [#19452](prometheus/prometheus#19452) - \[BUGFIX] TSDB: Fix WAL and GC log messages to emit human-readable duration strings instead of nanosecond integers. [#19307](prometheus/prometheus#19307) - \[BUGFIX] TSDB: Avoid WAL corruption after a failed WAL write in Agent mode. [#19700](prometheus/prometheus#19700) - \[BUGFIX] Agent: Ignore unknown WAL record types, to help users rolling back. [#19814](prometheus/prometheus#19814) </details> --- ### Configuration 📅 **Schedule**: (in timezone Europe/London) - Branch creation - At any time (no schedule defined) - Automerge - At any time (no schedule defined) 🚦 **Automerge**: Disabled by config. Please merge this manually once you are satisfied. ♻ **Rebasing**: Whenever PR becomes conflicted, or you tick the rebase/retry checkbox. 🔕 **Ignore**: Close this PR and you won't be reminded about this update again. --- - [ ] If you want to rebase/retry this PR, check this box --- This PR has been generated by [Mend Renovate CLI](https://github.com/renovatebot/renovate).  Reviewed-on: https://git.hayden.moe/hayden/phoebe/pulls/769

…➔ v3.15.0) (#2199) This PR contains the following updates: | Package | Update | Change | |---|---|---| | [quay.io/prometheus/prometheus](https://github.com/prometheus/prometheus) | minor | `v3.14.0` → `v3.15.0` | --- > ⚠️ **Warning** > > Some dependencies could not be looked up. Check the [Dependency Dashboard](issues/567) for more information. --- ### Release Notes <details> <summary>prometheus/prometheus (quay.io/prometheus/prometheus)</summary> ### [`v3.15.0`](https://github.com/prometheus/prometheus/releases/tag/v3.15.0): 3.15.0 / 2026-09-24 [Compare Source](prometheus/prometheus@v3.14.0...v3.15.0) - \[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](prometheus/prometheus#18081). [#18598](prometheus/prometheus#18598) - \[CHANGE] PromQL: Do not register a start timestamp reset if the start timestamp hasn't changed between subsequent samples. [#19454](prometheus/prometheus#19454) - \[CHANGE] Logging: Deprecate `--log.level`; use `runtime.log_level` configuration to supply the default level. [#19511](prometheus/prometheus#19511) - \[FEATURE] Configuration: Allow changing the process log level through `runtime.log_level` on configuration reload. [#19511](prometheus/prometheus#19511) - \[FEATURE] Prometheus: Add `--auto-gomemlimit.refresh-interval` flag to periodically re-detect the container or system memory limit and update `GOMEMLIMIT` at runtime. [#18843](prometheus/prometheus#18843) - \[FEATURE] Scraping: Add support for scraping targets via Unix Domain Sockets. [#12024](prometheus/prometheus#12024). [#18091](prometheus/prometheus#18091) - \[FEATURE] scrape: Implement OM2.0 scrape format. [#18606](prometheus/prometheus#18606) - \[ENHANCEMENT] Reduce TSDB head CPU utilization when initializing. [#18001](prometheus/prometheus#18001) - \[ENHANCEMENT] Docker SD: Add labels `__meta_docker_container_image` and `__meta_docker_container_image_id`. [#19386](prometheus/prometheus#19386) - \[ENHANCEMENT] Mixin: Add a p95/p99 remote-write send-batch latency panel to the remote-write dashboard. [#19500](prometheus/prometheus#19500) - \[ENHANCEMENT] Mixin: Support native histograms in the remote-write send-batch latency panel. [#19522](prometheus/prometheus#19522) - \[ENHANCEMENT] PromQL/TSDB: The `--enable-feature=st-storage` flag now automatically enables XOR2 float chunk encoding and ST-capable histogram chunk encoding, so you no longer need to pass `xor2-encoding` and `histograms-st-encoding` alongside it. [#19518](prometheus/prometheus#19518) - \[ENHANCEMENT] Remote write / Alertmanager: upgrade sigv4 to v0.5.0, adding `session_name` and `tags` fields for STS AssumeRole sessions. The previously undocumented `service_name` field is now also documented. [#19569](prometheus/prometheus#19569) - \[ENHANCEMENT] Scraping: Support zstd-compressed scrape responses, enabled via feature flag `zstd-scrape`. [#19502](prometheus/prometheus#19502) - \[ENHANCEMENT] TSDB: Stabilize the XOR2 float chunk encoding. `--enable-feature=xor2-encoding` is deprecated; use `storage.tsdb.chunk_encoding.floats: xor2` instead. Check that other software reading the TSDB directly (e.g. Thanos sidecar) supports XOR2 before enabling. [#19461](prometheus/prometheus#19461) - \[ENHANCEMENT] TSDB: add `prometheus_tsdb_head_appenders_created_total` metric. [#19411](prometheus/prometheus#19411) - \[ENHANCEMENT] Tracing: add more spans to scrapes, API queries and rule evaluations. [#19410](prometheus/prometheus#19410) - \[ENHANCEMENT] UI: Show the effective configuration for each scrape pool on the Targets and Service Discovery pages. [#19384](prometheus/prometheus#19384) - \[ENHANCEMENT] scrape: Enable start time synthesis for summary `_count` and `_sum` series in scrape appender v2. [#19323](prometheus/prometheus#19323) - \[ENHANCEMENT] scrape: stop all pools in parallel for faster shutdowns. [#19295](prometheus/prometheus#19295) - \[ENHANCEMENT] storage/remote: Add undocumented failed\_request\_logging config field to debug log remote write V2 requests on send errors. [#19249](prometheus/prometheus#19249) - \[ENHANCEMENT] TSDB: Add fast path for XOR chunk decompression to speed up queries. [#18049](prometheus/prometheus#18049) - \[ENHANCEMENT] UI: Improve native histogram table formatting and add a background bar indicating the bucket count. [#19332](prometheus/prometheus#19332) - \[ENHANCEMENT] TSDB: Add `prometheus_tsdb_head_series_pending_commit_underflow_total` to report pending-sample reservation underflows. [#19470](prometheus/prometheus#19470) - \[PERF] AWS SD: Build RDS cluster labels once per cluster instead of once per instance. [#19504](prometheus/prometheus#19504) - \[PERF] AWS SD: Describe RDS instances of different clusters concurrently, bounded by `request_concurrency`. [#19506](prometheus/prometheus#19506) - \[PERF] AWS SD: Describe each ElastiCache resource once per refresh instead of twice. [#19585](prometheus/prometheus#19585) - \[PERF] Remote read: Avoid cloning labels for sampled reads when no external labels are configured. [#19503](prometheus/prometheus#19503) - \[PERF] Remote write: Reuse OTLP converter scratch state between requests. [#19388](prometheus/prometheus#19388) - \[PERF] scrape: conversion from classic to native histograms should only parse start times when enabled. [#19446](prometheus/prometheus#19446) - \[BUGFIX] PromQL: Fix `info()` enrichment for composite expressions with mixed `@`/offset references or selector-free vector branches, preventing metadata from being evaluated at an unrelated timestamp. [#19387](prometheus/prometheus#19387) - \[BUGFIX] PromQL: Fix info() enrichment when input series use different subsets of identifying labels. [#19557](prometheus/prometheus#19557) - \[BUGFIX] PromQL: Preserve metric-name dropping through the info function when delayed name removal is enabled. [#19413](prometheus/prometheus#19413) - \[BUGFIX] TSDB: Don't silently drop samples when head garbage collection removes a series while it is being appended to. [#19272](prometheus/prometheus#19272) - \[BUGFIX] TSDB: Keep series with uncommitted samples during selected- and stale-series compaction, including when appenders overlap. [#19470](prometheus/prometheus#19470) - \[BUGFIX] TSDB: Do not retain head series after a synthetic start-timestamp zero sample is rejected. [#19470](prometheus/prometheus#19470) - \[BUGFIX] TSDB: Prevent query panics during series eviction after WAL replay. [#19664](prometheus/prometheus#19664) - \[BUGFIX] TSDB: fix potential deadlock between mmapSeriesChunks and gcSeries. [#19460](prometheus/prometheus#19460) - \[BUGFIX] TSDB: fix default block reload interval for custom options. [#19368](prometheus/prometheus#19368) - \[BUGFIX] AWS SD: Do not crash on serverless MSK clusters or MSK clusters without Open Monitoring. [#19194](prometheus/prometheus#19194) - \[BUGFIX] AWS SD: Do not panic when the ElastiCache API omits optional fields of a serverless cache or cache cluster. [#19435](prometheus/prometheus#19435) - \[BUGFIX] AWS SD: Reject non-positive `request_concurrency` instead of hanging service discovery indefinitely. [#19524](prometheus/prometheus#19524) - \[BUGFIX] Discovery/AWS: Avoid a panic when discovering standalone ECS tasks with custom task groups. [#19302](prometheus/prometheus#19302) - \[BUGFIX] Discovery: Do not panic in AWS Lightsail service discovery when an instance is missing optional fields such as availability zone, blueprint, bundle, name, state or support code. [#19324](prometheus/prometheus#19324) - \[BUGFIX] Discovery: delete the stale `prometheus_sd_last_update_timestamp_seconds` series for a config that is removed on reload. [#19131](prometheus/prometheus#19131) - \[BUGFIX] HTTP: Avoid truncating compressed responses when handlers set Content-Length. [#19661](prometheus/prometheus#19661) - \[BUGFIX] IONOS SD: Do not panic when the API response omits the server, NIC or volume collections, or a server's properties. [#19438](prometheus/prometheus#19438) - \[BUGFIX] Metadata will not affect the number of Remote Write v2 shards. [#19218](prometheus/prometheus#19218) - \[BUGFIX] Mixins: Fix label mismatches that prevented PrometheusHAGroupNotIngestingSamples and PrometheusHAGroupCrashlooping from firing. [#19444](prometheus/prometheus#19444) - \[BUGFIX] Native histograms: `DetectReset` no longer misses a counter reset when a populated bucket behind an empty one disappears, which could make histogram `rate()`/`increase()` undercount. [#19367](prometheus/prometheus#19367) - \[BUGFIX] Never skip histogram buckets for histogram\_stddev and histogram\_stdvar functions. [#19521](prometheus/prometheus#19521) - \[BUGFIX] OTLP: Do not abort an entire OTLP payload ingestion if one metric has no datapoints. [#19343](prometheus/prometheus#19343) - \[BUGFIX] PromQL: Fix FastRegexMatcher false-positive match when a capturing group is directly adjacent to a literal (e.g. `.*\|(foo)\|.*`). [#19516](prometheus/prometheus#19516) - \[BUGFIX] PromQL: Fix a panic in range selectors using the experimental `anchored` or `smoothed` modifier when the selected series has no samples inside the query window, for example a query evaluated inside a scrape gap. [#19431](prometheus/prometheus#19431) - \[BUGFIX] PromQL: Fix empty results when a subquery with `@` is used as the matrix argument of a call that is not step-invariant (for example `quantile_over_time(scalar(x), metric[...:...] @ T)`). [#19187](prometheus/prometheus#19187) - \[BUGFIX] PromQL: Make the "found duplicate series for the match group" many-to-many matching error message deterministic by sorting the two duplicate labels. [#18810](prometheus/prometheus#18810) - \[BUGFIX] PromQL: Preserve parentheses around duration literals on Expr.String() round-trip. [#19403](prometheus/prometheus#19403) - \[BUGFIX] PromQL: Reject duration-expression offsets and `@ start()` / `@ end()` before range selectors, matching the existing rejection of literal offsets and `@ <timestamp>`. [#19406](prometheus/prometheus#19406) - \[BUGFIX] PromQL: Report the position of the histogram argument rather than of a scalar argument in the native histogram NaN observation annotations of `histogram_quantile` and `histogram_fraction`. [#19330](prometheus/prometheus#19330) - \[BUGFIX] PromQL: info() now applies the @ modifier/offset when evaluating the info series, so info(v @ T) enriches as of T consistently instead of depending on the query start/eval time. [#19266](prometheus/prometheus#19266) - \[BUGFIX] Rules: Fix a panic when a rule manager created without a logger loads a rule file containing multiple YAML documents. [#19433](prometheus/prometheus#19433) - \[BUGFIX] Scrape: Do not append a stale marker for a series that is still exposed when the storage returns a new series reference for it. [#19328](prometheus/prometheus#19328) - \[BUGFIX] Scrape: JSON log formatter correctly format scrape target info. [#19472](prometheus/prometheus#19472) - \[BUGFIX] TSDB: Fix in-order chunk ID overflow by wrapping head chunk IDs modulo 2^23 so they never collide with the out-of-order flag bit. [#19450](prometheus/prometheus#19450) - \[BUGFIX] TSDB: Fix out-of-order chunk ID overflow by wrapping `firstOOOChunkID` modulo 2^23 instead of growing unbounded. [#19216](prometheus/prometheus#19216) - \[BUGFIX] UI: Remove an extraneous X-axis tick mark in the native histogram chart when using the "linear" display mode. [#19326](prometheus/prometheus#19326) - \[BUGFIX] discovery/aws: Avoid a panic when an ElastiCache ARN is missing its resource ID. [#19333](prometheus/prometheus#19333) - \[BUGFIX] discovery/aws: Do not panic on MSK clusters whose optional API fields are absent. [#19584](prometheus/prometheus#19584) - \[BUGFIX] discovery/aws: Do not panic when the EC2 API omits optional instance fields. [#19512](prometheus/prometheus#19512) - \[BUGFIX] discovery/aws: Don't panic on ECS tasks with absent optional fields. [#19396](prometheus/prometheus#19396) - \[BUGFIX] discovery/aws: MSK Optional Custom Configuration Fields [#19422](prometheus/prometheus#19422). [#19422](prometheus/prometheus#19422) - \[BUGFIX] discovery/ionos: Fix panic when the IONOS API omits optional server fields. [#19418](prometheus/prometheus#19418) - \[BUGFIX] discovery/kubernetes: Populate `__meta_kubernetes_service_loadbalancer_ip` from `status.loadBalancer.ingress`, falling back to deprecated `spec.loadBalancerIP`. [#19404](prometheus/prometheus#19404) - \[BUGFIX] histogram: Fix Compact moving buckets to wrong indices, and producing negative bucket counts for integer histograms, when more than one span is merged in the same pass. [#19312](prometheus/prometheus#19312) - \[BUGFIX] promtool: Fixed `tsdb dump` silently dropping native histogram samples. [#18051](prometheus/prometheus#18051) - \[BUGFIX] scrape: fix data race in `Manager.TargetsDroppedCounts` to avoid miscounting dropped targets. [#19304](prometheus/prometheus#19304) - \[BUGFIX] scrape: fix nil histogram when native and classic histograms are mixed in one metric family. [#19452](prometheus/prometheus#19452) - \[BUGFIX] TSDB: Fix WAL and GC log messages to emit human-readable duration strings instead of nanosecond integers. [#19307](prometheus/prometheus#19307) - \[BUGFIX] TSDB: Avoid WAL corruption after a failed WAL write in Agent mode. [#19700](prometheus/prometheus#19700) - \[BUGFIX] Agent: Ignore unknown WAL record types, to help users rolling back. [#19814](prometheus/prometheus#19814) </details> --- ### Configuration 📅 **Schedule**: (in timezone Europe/Paris) - Branch creation - At any time (no schedule defined) - Automerge - At any time (no schedule defined) 🚦 **Automerge**: Disabled by config. Please merge this manually once you are satisfied. ♻ **Rebasing**: Whenever PR becomes conflicted, or you tick the rebase/retry checkbox. 🔕 **Ignore**: Close this PR and you won't be reminded about this update again. --- - [ ] If you want to rebase/retry this PR, check this box --- This PR has been generated by [Mend Renovate CLI](https://github.com/renovatebot/renovate).  Reviewed-on: https://git.erwanleboucher.dev/eleboucher/homelab/pulls/2199

sueun-dev requested review from a team and krajorama as code owners August 8, 2026 08:52

linasm approved these changes Aug 11, 2026

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vpranckaitis approved these changes Aug 11, 2026

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krajorama merged commit f94c403 into prometheus:main Aug 12, 2026
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B0go mentioned this pull request Aug 31, 2026

downsample: support changing custom bucket layouts basecamp/thanos#1

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B0go mentioned this pull request Sep 1, 2026

downsample: apply reset semantics when a delta regresses basecamp/thanos#3

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github-actions Bot mentioned this pull request Oct 19, 2026

Update prom/prometheus Docker tag to v3.15.0 claytono/infra#3239

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fix(model/histogram): do not miss counter resets behind empty buckets in DetectReset - #19367

fix(model/histogram): do not miss counter resets behind empty buckets in DetectReset#19367
krajorama merged 1 commit into
prometheus:mainfrom
sueun-dev:fix-floathistogram-detectreset-empty-bucket

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sueun-dev commented Aug 8, 2026

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