instrumentation: add native histograms to complement high-traffic summaries#17374
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beorn7 merged 12 commits intoprometheus:mainfrom Nov 27, 2025
Merged
instrumentation: add native histograms to complement high-traffic summaries#17374beorn7 merged 12 commits intoprometheus:mainfrom
beorn7 merged 12 commits intoprometheus:mainfrom
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Pull Request Overview
This PR introduces native histogram variants for several high-traffic internal metrics in Prometheus to complement existing summary metrics. The change addresses performance concerns with summaries under high cardinality by providing histogram alternatives that are more efficient at scale.
Key Changes:
- Added native histogram metrics alongside existing summary metrics for timing measurements
- Configured histograms with consistent bucketing (0.01, 0.1, 1, 10 seconds) and native histogram parameters
- Existing summary metrics are retained to maintain backward compatibility
Reviewed Changes
Copilot reviewed 10 out of 10 changed files in this pull request and generated no comments.
Show a summary per file
| File | Description |
|---|---|
| scrape/scrape.go | Added histogram observations for target sync and scrape interval measurements |
| scrape/metrics.go | Defined new histogram metrics for scrape pool sync and interval timing |
| rules/manager.go | Added histogram observation for rule group iteration duration |
| rules/group.go | Defined histogram metrics for rule evaluation and iteration timing |
| promql/engine.go | Added histogram metrics for query timing phases (queue, prepare, eval, sort) |
| notifier/metric.go | Defined histogram metric for alert notification latency |
| notifier/manager.go | Added histogram observation for notification send latency |
| discovery/refresh/refresh.go | Added histogram observation for service discovery refresh duration |
| discovery/metrics_refresh.go | Defined histogram metric for SD refresh timing |
| discovery/discovery.go | Added histogram observer field to RefreshMetrics struct |
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Thank you very much. Mostly naming nits, but I also found a few omissions for deregistering and such.
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Thanks. Looks good now. However, you are also adding the same histogram here as in the much older #16637, which was the PR that inspired #17332. To play fair, let's wait for #16637 to get merged first, or alternatively you could remove the changes that mirror the one in #16637 from this PR. Final request: Could you adjust the |
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#16637 is merged. Could you rebase this? Thank you. |
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@hxrshxz are you still on this? There is very little left to do here. |
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Hey sorry I was actually busy with my university exams , I will update the PR tomorrow , thank you so much for waiting |
…ry, notifier, rules, and scrape packages Signed-off-by: Harsh <harshmastic@gmail.com>
Co-authored-by: Björn Rabenstein <github@rabenste.in> Signed-off-by: harsh kumar <135993950+hxrshxz@users.noreply.github.com>
Co-authored-by: Björn Rabenstein <github@rabenste.in> Signed-off-by: harsh kumar <135993950+hxrshxz@users.noreply.github.com>
Co-authored-by: Björn Rabenstein <github@rabenste.in> Signed-off-by: harsh kumar <135993950+hxrshxz@users.noreply.github.com>
Co-authored-by: Björn Rabenstein <github@rabenste.in> Signed-off-by: harsh kumar <135993950+hxrshxz@users.noreply.github.com>
Co-authored-by: Björn Rabenstein <github@rabenste.in> Signed-off-by: harsh kumar <135993950+hxrshxz@users.noreply.github.com>
Co-authored-by: Björn Rabenstein <github@rabenste.in> Signed-off-by: harsh kumar <135993950+hxrshxz@users.noreply.github.com>
Co-authored-by: Björn Rabenstein <github@rabenste.in> Signed-off-by: harsh kumar <135993950+hxrshxz@users.noreply.github.com>
Co-authored-by: Björn Rabenstein <github@rabenste.in> Signed-off-by: harsh kumar <135993950+hxrshxz@users.noreply.github.com>
Co-authored-by: Björn Rabenstein <github@rabenste.in> Signed-off-by: harsh kumar <135993950+hxrshxz@users.noreply.github.com>
Co-authored-by: Björn Rabenstein <github@rabenste.in> Signed-off-by: harsh kumar <135993950+hxrshxz@users.noreply.github.com>
…s various components Signed-off-by: Harsh <harshmastic@gmail.com>
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Code looks great now, but could you address my comment about the release notes in the commit description? It should look like this: Filling in all the new histogram names (unless that's a very long list, but I think it's feasible – we have done similar changelog notes before. It's very handy if users can see directly the new metric names in the changelog). |
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Really sorry I completely missed the comment about updating the PR description 😅 |
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Great. Thank you. (I have corrected one metric name in the PR description.)
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##### [\`v3.9.0\`](https://github.com/prometheus/prometheus/releases/tag/v3.9.0) #### Note for users of Native Histograms In version 3.9, Native Histograms is no longer experimental, and the feature flag `native-histogram` has no effect. You must now turn on the config setting `scrape_native_histograms` to collect Native Histogram samples from exporters. #### Changelog - \[CHANGE] Native Histograms are no longer experimental! Make the `native-histogram` feature flag a no-op. Use `scrape_native_histograms` config option instead. [#17528](prometheus/prometheus#17528) - \[CHANGE] API: Add maximum limit of 10,000 sets of statistics to TSDB status endpoint. [#17647](prometheus/prometheus#17647) - \[FEATURE] API: Add /api/v1/features for clients to understand which features are supported. [#17427](prometheus/prometheus#17427) - \[FEATURE] Promtool: Add `start_timestamp` field for unit tests. [#17636](prometheus/prometheus#17636) - \[FEATURE] Promtool: Add `--format seriesjson` option to `tsdb dump` to output just series labels in JSON format. [#13409](prometheus/prometheus#13409) - \[FEATURE] Add `--storage.tsdb.delay-compact-file.path` flag for better interoperability with Thanos. [#17435](prometheus/prometheus#17435) - \[FEATURE] UI: Add an option on the query drop-down menu to duplicate that query panel. [#17714](prometheus/prometheus#17714) - \[ENHANCEMENT]: TSDB: add flag `--storage.tsdb.block-reload-interval` to configure TSDB Block Reload Interval. [#16728](prometheus/prometheus#16728) - \[ENHANCEMENT] UI: Add graph option to start the chart's Y axis at zero. [#17565](prometheus/prometheus#17565) - \[ENHANCEMENT] Scraping: Classic protobuf format no longer requires the unit in the metric name. [#16834](prometheus/prometheus#16834) - \[ENHANCEMENT] PromQL, Rules, SD, Scraping: Add native histograms to complement existing summaries. [#17374](prometheus/prometheus#17374) - \[ENHANCEMENT] Notifications: Add a histogram `prometheus_notifications_latency_histogram_seconds` to complement the existing summary. [#16637](prometheus/prometheus#16637) - \[ENHANCEMENT] Remote-write: Add custom scope support for AzureAD authentication. [#17483](prometheus/prometheus#17483) - \[ENHANCEMENT] SD: add a `config` label with job name for most `prometheus_sd_refresh` metrics. [#17138](prometheus/prometheus#17138) - \[ENHANCEMENT] TSDB: New histogram `prometheus_tsdb_sample_ooo_delta`, the distribution of out-of-order samples in seconds. Collected for all samples, accepted or not. [#17477](prometheus/prometheus#17477) - \[ENHANCEMENT] Remote-read: Validate histograms received via remote-read. [#17561](prometheus/prometheus#17561) - \[PERF] TSDB: Small optimizations to postings index. [#17439](prometheus/prometheus#17439) - \[PERF] Scraping: Speed up relabelling of series. [#17530](prometheus/prometheus#17530) - \[PERF] PromQL: Small optimisations in binary operators. [#17524](prometheus/prometheus#17524), [#17519](prometheus/prometheus#17519). - \[BUGFIX] UI: PromQL autocomplete now shows the correct type and HELP text for OpenMetrics counters whose samples end in `_total`. [#17682](prometheus/prometheus#17682) - \[BUGFIX] UI: Fixed codemirror-promql incorrectly showing label completion suggestions after the closing curly brace of a vector selector. [#17602](prometheus/prometheus#17602) - \[BUGFIX] UI: Query editor no longer suggests a duration unit if one is already present after a number. [#17605](prometheus/prometheus#17605) - \[BUGFIX] PromQL: Fix some "vector cannot contain metrics with the same labelset" errors when experimental delayed name removal is enabled. [#17678](prometheus/prometheus#17678) - \[BUGFIX] PromQL: Fix possible corruption of PromQL text if the query had an empty `ignoring()` and non-empty grouping. [#17643](prometheus/prometheus#17643) - \[BUGFIX] PromQL: Fix resets/changes to return empty results for anchored selectors when all samples are outside the range. [#17479](prometheus/prometheus#17479) - \[BUGFIX] PromQL: Check more consistently for many-to-one matching in filter binary operators. [#17668](prometheus/prometheus#17668) - \[BUGFIX] PromQL: Fix collision in unary negation with non-overlapping series. [#17708](prometheus/prometheus#17708) - \[BUGFIX] PromQL: Fix collision in label\_join and label\_replace with non-overlapping series. [#17703](prometheus/prometheus#17703) - \[BUGFIX] PromQL: Fix bug with inconsistent results for queries with OR expression when experimental delayed name removal is enabled. [#17161](prometheus/prometheus#17161) - \[BUGFIX] PromQL: Ensure that `rate`/`increase`/`delta` of histograms results in a gauge histogram. [#17608](prometheus/prometheus#17608) - \[BUGFIX] PromQL: Do not panic while iterating over invalid histograms. [#17559](prometheus/prometheus#17559) - \[BUGFIX] TSDB: Reject chunk files whose encoded chunk length overflows int. [#17533](prometheus/prometheus#17533) - \[BUGFIX] TSDB: Do not panic during resolution reduction of invalid histograms. [#17561](prometheus/prometheus#17561) - \[BUGFIX] Remote-write Receive: Avoid duplicate labels when experimental type-and-unit-label feature is enabled. [#17546](prometheus/prometheus#17546) - \[BUGFIX] OTLP Receiver: Only write metadata to disk when experimental metadata-wal-records feature is enabled. [#17472](prometheus/prometheus#17472)
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##### [\`v3.9.1\`](https://github.com/prometheus/prometheus/releases/tag/v3.9.1) - \[BUGFIX] Agent: fix crash shortly after startup from invalid type of object. [#17802](prometheus/prometheus#17802) - \[BUGFIX] Scraping: fix relabel keep/drop not working. [#17807](prometheus/prometheus#17807) --- ##### [\`v3.9.0\`](https://github.com/prometheus/prometheus/releases/tag/v3.9.0) #### Note for users of Native Histograms In version 3.9, Native Histograms is no longer experimental, and the feature flag `native-histogram` has no effect. You must now turn on the config setting `scrape_native_histograms` to collect Native Histogram samples from exporters. #### Changelog - \[CHANGE] Native Histograms are no longer experimental! Make the `native-histogram` feature flag a no-op. Use `scrape_native_histograms` config option instead. [#17528](prometheus/prometheus#17528) - \[CHANGE] API: Add maximum limit of 10,000 sets of statistics to TSDB status endpoint. [#17647](prometheus/prometheus#17647) - \[FEATURE] API: Add /api/v1/features for clients to understand which features are supported. [#17427](prometheus/prometheus#17427) - \[FEATURE] Promtool: Add `start_timestamp` field for unit tests. [#17636](prometheus/prometheus#17636) - \[FEATURE] Promtool: Add `--format seriesjson` option to `tsdb dump` to output just series labels in JSON format. [#13409](prometheus/prometheus#13409) - \[FEATURE] Add `--storage.tsdb.delay-compact-file.path` flag for better interoperability with Thanos. [#17435](prometheus/prometheus#17435) - \[FEATURE] UI: Add an option on the query drop-down menu to duplicate that query panel. [#17714](prometheus/prometheus#17714) - \[ENHANCEMENT]: TSDB: add flag `--storage.tsdb.block-reload-interval` to configure TSDB Block Reload Interval. [#16728](prometheus/prometheus#16728) - \[ENHANCEMENT] UI: Add graph option to start the chart's Y axis at zero. [#17565](prometheus/prometheus#17565) - \[ENHANCEMENT] Scraping: Classic protobuf format no longer requires the unit in the metric name. [#16834](prometheus/prometheus#16834) - \[ENHANCEMENT] PromQL, Rules, SD, Scraping: Add native histograms to complement existing summaries. [#17374](prometheus/prometheus#17374) - \[ENHANCEMENT] Notifications: Add a histogram `prometheus_notifications_latency_histogram_seconds` to complement the existing summary. [#16637](prometheus/prometheus#16637) - \[ENHANCEMENT] Remote-write: Add custom scope support for AzureAD authentication. [#17483](prometheus/prometheus#17483) - \[ENHANCEMENT] SD: add a `config` label with job name for most `prometheus_sd_refresh` metrics. [#17138](prometheus/prometheus#17138) - \[ENHANCEMENT] TSDB: New histogram `prometheus_tsdb_sample_ooo_delta`, the distribution of out-of-order samples in seconds. Collected for all samples, accepted or not. [#17477](prometheus/prometheus#17477) - \[ENHANCEMENT] Remote-read: Validate histograms received via remote-read. [#17561](prometheus/prometheus#17561) - \[PERF] TSDB: Small optimizations to postings index. [#17439](prometheus/prometheus#17439) - \[PERF] Scraping: Speed up relabelling of series. [#17530](prometheus/prometheus#17530) - \[PERF] PromQL: Small optimisations in binary operators. [#17524](prometheus/prometheus#17524), [#17519](prometheus/prometheus#17519). - \[BUGFIX] UI: PromQL autocomplete now shows the correct type and HELP text for OpenMetrics counters whose samples end in `_total`. [#17682](prometheus/prometheus#17682) - \[BUGFIX] UI: Fixed codemirror-promql incorrectly showing label completion suggestions after the closing curly brace of a vector selector. [#17602](prometheus/prometheus#17602) - \[BUGFIX] UI: Query editor no longer suggests a duration unit if one is already present after a number. [#17605](prometheus/prometheus#17605) - \[BUGFIX] PromQL: Fix some "vector cannot contain metrics with the same labelset" errors when experimental delayed name removal is enabled. [#17678](prometheus/prometheus#17678) - \[BUGFIX] PromQL: Fix possible corruption of PromQL text if the query had an empty `ignoring()` and non-empty grouping. [#17643](prometheus/prometheus#17643) - \[BUGFIX] PromQL: Fix resets/changes to return empty results for anchored selectors when all samples are outside the range. [#17479](prometheus/prometheus#17479) - \[BUGFIX] PromQL: Check more consistently for many-to-one matching in filter binary operators. [#17668](prometheus/prometheus#17668) - \[BUGFIX] PromQL: Fix collision in unary negation with non-overlapping series. [#17708](prometheus/prometheus#17708) - \[BUGFIX] PromQL: Fix collision in label\_join and label\_replace with non-overlapping series. [#17703](prometheus/prometheus#17703) - \[BUGFIX] PromQL: Fix bug with inconsistent results for queries with OR expression when experimental delayed name removal is enabled. [#17161](prometheus/prometheus#17161) - \[BUGFIX] PromQL: Ensure that `rate`/`increase`/`delta` of histograms results in a gauge histogram. [#17608](prometheus/prometheus#17608) - \[BUGFIX] PromQL: Do not panic while iterating over invalid histograms. [#17559](prometheus/prometheus#17559) - \[BUGFIX] TSDB: Reject chunk files whose encoded chunk length overflows int. [#17533](prometheus/prometheus#17533) - \[BUGFIX] TSDB: Do not panic during resolution reduction of invalid histograms. [#17561](prometheus/prometheus#17561) - \[BUGFIX] Remote-write Receive: Avoid duplicate labels when experimental type-and-unit-label feature is enabled. [#17546](prometheus/prometheus#17546) - \[BUGFIX] OTLP Receiver: Only write metadata to disk when experimental metadata-wal-records feature is enabled. [#17472](prometheus/prometheus#17472)
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##### [\`v3.9.1\`](https://github.com/prometheus/prometheus/releases/tag/v3.9.1) - \[BUGFIX] Agent: fix crash shortly after startup from invalid type of object. [#17802](prometheus/prometheus#17802) - \[BUGFIX] Scraping: fix relabel keep/drop not working. [#17807](prometheus/prometheus#17807) --- ##### [\`v3.9.0\`](https://github.com/prometheus/prometheus/releases/tag/v3.9.0) #### Note for users of Native Histograms In version 3.9, Native Histograms is no longer experimental, and the feature flag `native-histogram` has no effect. You must now turn on the config setting `scrape_native_histograms` to collect Native Histogram samples from exporters. #### Changelog - \[CHANGE] Native Histograms are no longer experimental! Make the `native-histogram` feature flag a no-op. Use `scrape_native_histograms` config option instead. [#17528](prometheus/prometheus#17528) - \[CHANGE] API: Add maximum limit of 10,000 sets of statistics to TSDB status endpoint. [#17647](prometheus/prometheus#17647) - \[FEATURE] API: Add /api/v1/features for clients to understand which features are supported. [#17427](prometheus/prometheus#17427) - \[FEATURE] Promtool: Add `start_timestamp` field for unit tests. [#17636](prometheus/prometheus#17636) - \[FEATURE] Promtool: Add `--format seriesjson` option to `tsdb dump` to output just series labels in JSON format. [#13409](prometheus/prometheus#13409) - \[FEATURE] Add `--storage.tsdb.delay-compact-file.path` flag for better interoperability with Thanos. [#17435](prometheus/prometheus#17435) - \[FEATURE] UI: Add an option on the query drop-down menu to duplicate that query panel. [#17714](prometheus/prometheus#17714) - \[ENHANCEMENT]: TSDB: add flag `--storage.tsdb.block-reload-interval` to configure TSDB Block Reload Interval. [#16728](prometheus/prometheus#16728) - \[ENHANCEMENT] UI: Add graph option to start the chart's Y axis at zero. [#17565](prometheus/prometheus#17565) - \[ENHANCEMENT] Scraping: Classic protobuf format no longer requires the unit in the metric name. [#16834](prometheus/prometheus#16834) - \[ENHANCEMENT] PromQL, Rules, SD, Scraping: Add native histograms to complement existing summaries. [#17374](prometheus/prometheus#17374) - \[ENHANCEMENT] Notifications: Add a histogram `prometheus_notifications_latency_histogram_seconds` to complement the existing summary. [#16637](prometheus/prometheus#16637) - \[ENHANCEMENT] Remote-write: Add custom scope support for AzureAD authentication. [#17483](prometheus/prometheus#17483) - \[ENHANCEMENT] SD: add a `config` label with job name for most `prometheus_sd_refresh` metrics. [#17138](prometheus/prometheus#17138) - \[ENHANCEMENT] TSDB: New histogram `prometheus_tsdb_sample_ooo_delta`, the distribution of out-of-order samples in seconds. Collected for all samples, accepted or not. [#17477](prometheus/prometheus#17477) - \[ENHANCEMENT] Remote-read: Validate histograms received via remote-read. [#17561](prometheus/prometheus#17561) - \[PERF] TSDB: Small optimizations to postings index. [#17439](prometheus/prometheus#17439) - \[PERF] Scraping: Speed up relabelling of series. [#17530](prometheus/prometheus#17530) - \[PERF] PromQL: Small optimisations in binary operators. [#17524](prometheus/prometheus#17524), [#17519](prometheus/prometheus#17519). - \[BUGFIX] UI: PromQL autocomplete now shows the correct type and HELP text for OpenMetrics counters whose samples end in `_total`. [#17682](prometheus/prometheus#17682) - \[BUGFIX] UI: Fixed codemirror-promql incorrectly showing label completion suggestions after the closing curly brace of a vector selector. [#17602](prometheus/prometheus#17602) - \[BUGFIX] UI: Query editor no longer suggests a duration unit if one is already present after a number. [#17605](prometheus/prometheus#17605) - \[BUGFIX] PromQL: Fix some "vector cannot contain metrics with the same labelset" errors when experimental delayed name removal is enabled. [#17678](prometheus/prometheus#17678) - \[BUGFIX] PromQL: Fix possible corruption of PromQL text if the query had an empty `ignoring()` and non-empty grouping. [#17643](prometheus/prometheus#17643) - \[BUGFIX] PromQL: Fix resets/changes to return empty results for anchored selectors when all samples are outside the range. [#17479](prometheus/prometheus#17479) - \[BUGFIX] PromQL: Check more consistently for many-to-one matching in filter binary operators. [#17668](prometheus/prometheus#17668) - \[BUGFIX] PromQL: Fix collision in unary negation with non-overlapping series. [#17708](prometheus/prometheus#17708) - \[BUGFIX] PromQL: Fix collision in label\_join and label\_replace with non-overlapping series. [#17703](prometheus/prometheus#17703) - \[BUGFIX] PromQL: Fix bug with inconsistent results for queries with OR expression when experimental delayed name removal is enabled. [#17161](prometheus/prometheus#17161) - \[BUGFIX] PromQL: Ensure that `rate`/`increase`/`delta` of histograms results in a gauge histogram. [#17608](prometheus/prometheus#17608) - \[BUGFIX] PromQL: Do not panic while iterating over invalid histograms. [#17559](prometheus/prometheus#17559) - \[BUGFIX] TSDB: Reject chunk files whose encoded chunk length overflows int. [#17533](prometheus/prometheus#17533) - \[BUGFIX] TSDB: Do not panic during resolution reduction of invalid histograms. [#17561](prometheus/prometheus#17561) - \[BUGFIX] Remote-write Receive: Avoid duplicate labels when experimental type-and-unit-label feature is enabled. [#17546](prometheus/prometheus#17546) - \[BUGFIX] OTLP Receiver: Only write metadata to disk when experimental metadata-wal-records feature is enabled. [#17472](prometheus/prometheus#17472)
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Which issue(s) does the PR fix:
addresses #17332
Does this PR introduce a user-facing change?