update doc and changelog

Signed-off-by: Ben Ye <[email protected]>

Author: yeya24

CHANGELOG.md

@@ -9,6 +9,7 @@
 * [FEATURE] Query Frontend: Added a query rejection mechanism to block resource-intensive queries. #6005
 * [FEATURE] OTLP: Support ingesting OTLP exponential metrics as native histograms. #6071
 * [FEATURE] Ingester: Add `ingester.instance-limits.max-inflight-query-requests` to allow limiting ingester concurrent queries. #6081
+* [FEATURE] Distributor: Add `validation.max-native-histogram-buckets` to limit max number of bucket count. Distributor will try to automatically reduce histogram resolution until it is within the bucket limit or resolution cannot be reduced anymore. #6104
 * [ENHANCEMENT] rulers: Add support to persist tokens in rulers. #5987
 * [ENHANCEMENT] Query Frontend/Querier: Added store gateway postings touched count and touched size in Querier stats and log in Query Frontend. #5892
 * [ENHANCEMENT] Query Frontend/Querier: Returns `warnings` on prometheus query responses. #5916

docs/configuration/config-file-reference.md

@@ -3159,11 +3159,13 @@ The `limits_config` configures default and per-tenant limits imposed by Cortex s
 # e.g. remote_write.write_relabel_configs.
 [metric_relabel_configs: <relabel_config...> | default = []]
 
-# Enables support for exemplars in TSDB and sets the maximum number that will be
-# stored. less than zero means disabled. If the value is set to zero, cortex
-# will fallback to blocks-storage.tsdb.max-exemplars value.
-# CLI flag: -ingester.max-exemplars
-[max_exemplars: <int> | default = 0]
+# Limit on total number of positive and negative buckets allowed in a single
+# native histogram. The resolution of a histogram with more buckets will be
+# reduced until the number of buckets is within the limit. If the limit cannot
+# be reached, the sample will be discarded. 0 means no limit. Enforced at
+# Distributor.
+# CLI flag: -validation.max-native-histogram-buckets
+[max_native_histogram_buckets: <int> | default = 0]
 
 # The maximum number of active series per user, per ingester. 0 to disable.
 # CLI flag: -ingester.max-series-per-user
@@ -3213,6 +3215,12 @@ The `limits_config` configures default and per-tenant limits imposed by Cortex s
 # CLI flag: -ingester.out-of-order-time-window
 [out_of_order_time_window: <duration> | default = 0s]
 
+# Enables support for exemplars in TSDB and sets the maximum number that will be
+# stored. less than zero means disabled. If the value is set to zero, cortex
+# will fallback to blocks-storage.tsdb.max-exemplars value.
+# CLI flag: -ingester.max-exemplars
+[max_exemplars: <int> | default = 0]
+
 # Maximum number of chunks that can be fetched in a single query from ingesters
 # and long-term storage. This limit is enforced in the querier, ruler and
 # store-gateway. 0 to disable.

pkg/util/validation/limits.go

@@ -234,7 +234,7 @@ func (l *Limits) RegisterFlags(f *flag.FlagSet) {
 	f.Var(&l.CreationGracePeriod, "validation.create-grace-period", "Duration which table will be created/deleted before/after it's needed; we won't accept sample from before this time.")
 	f.BoolVar(&l.EnforceMetricName, "validation.enforce-metric-name", true, "Enforce every sample has a metric name.")
 	f.BoolVar(&l.EnforceMetadataMetricName, "validation.enforce-metadata-metric-name", true, "Enforce every metadata has a metric name.")
-	f.IntVar(&l.MaxNativeHistogramBuckets, "validation.max-native-histogram-buckets", 0, ".")
+	f.IntVar(&l.MaxNativeHistogramBuckets, "validation.max-native-histogram-buckets", 0, "Limit on total number of positive and negative buckets allowed in a single native histogram. The resolution of a histogram with more buckets will be reduced until the number of buckets is within the limit. If the limit cannot be reached, the sample will be discarded. 0 means no limit. Enforced at Distributor.")
 
 	f.IntVar(&l.MaxLocalSeriesPerUser, "ingester.max-series-per-user", 5000000, "The maximum number of active series per user, per ingester. 0 to disable.")
 	f.IntVar(&l.MaxLocalSeriesPerMetric, "ingester.max-series-per-metric", 50000, "The maximum number of active series per metric name, per ingester. 0 to disable.")