* SECURITY: upgrade Go builder from Go1.21.5 to Go1.21.6. See [the list of issues addressed in Go1.21.6](https://github.com/golang/go/issues?q=milestone%3AGo1.21.6+label%3ACherryPickApproved).
* FEATURE: improve new [time series](https://docs.victoriametrics.com/keyConcepts.html#time-series) registration speed on systems with high number of CPU cores. Thanks to @misutoth for the initial idea and [implementation](https://github.com/VictoriaMetrics/VictoriaMetrics/pull/5212).
* FEATURE: make [background merge](https://docs.victoriametrics.com/#storage) more responsive and scalable. This should help the following issues: [5190](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/5190), [3425](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/3425), [648](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/648).
* FEATURE: [graphite](https://docs.victoriametrics.com/#graphite-render-api-usage): add support for negative index in `groupByNode` and `aliasByNode` functions. Thanks to @rbizos for [the pull request](https://github.com/VictoriaMetrics/VictoriaMetrics/pull/5581).
* FEATURE: [vmagent](https://docs.victoriametrics.com/vmagent.html): add support for discovering [Hetzner Cloud](https://www.hetzner.com/cloud) and [Hetzner Robot](https://docs.hetzner.com/robot) scrape targets. See [this feature request](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/3154) and [these docs](https://docs.victoriametrics.com/sd_configs.html#hetzner_sd_configs).
* FEATURE: [vmagent](https://docs.victoriametrics.com/vmagent.html): add support for [DataDog v2 data ingestion protocol](https://docs.datadoghq.com/api/latest/metrics/#submit-metrics). See [these docs](https://docs.victoriametrics.com/#how-to-send-data-from-datadog-agent) and [this feature request](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/4451).
* FEATURE: [vmagent](https://docs.victoriametrics.com/vmagent.html): reduce initial memory usage when scraping targets, which return huge responses (for example, [kube-state-metrics](https://github.com/kubernetes/kube-state-metrics) in large Kubernetes cluster may return 100MB+ responses), without the need to explicitly enable [stream parsing mode](https://docs.victoriametrics.com/vmagent/#stream-parsing-mode). See [this issue](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/5567).
* FEATURE: [vmagent](https://docs.victoriametrics.com/vmagent.html): expose ability to set OAuth2 endpoint parameters per each `-remoteWrite.url` via the command-line flag `-remoteWrite.oauth2.endpointParams`. See [these docs](https://docs.victoriametrics.com/vmagent.html#advanced-usage). Thanks to @mhill-holoplot for the [pull request](https://github.com/VictoriaMetrics/VictoriaMetrics/pull/5427).
* FEATURE: [vmagent](https://docs.victoriametrics.com/vmagent.html): add ability to set `attach_metadata.node=true` option for all the [`kubernetes_sd_configs`](https://docs.victoriametrics.com/sd_configs.html#kubernetes_sd_configs) defined at [`-promscrape.config`](https://docs.victoriametrics.com/vmagent.html#quick-start) via `-promscrape.kubernetes.attachNodeMetadataAll` command-line flag. See [this feature request](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/4640). Thanks to @wasim-nihal for [the initial implementation](https://github.com/VictoriaMetrics/VictoriaMetrics/pull/5593).
* FEATURE: [vmagent](https://docs.victoriametrics.com/vmagent.html): do not send unfinished [aggregation state](https://docs.victoriametrics.com/stream-aggregation.html) on shutdown or [hot config reload](https://docs.victoriametrics.com/stream-aggregation.html#configuration-update) by default, as it tend to produce unexpected anomalies with lower values. The old behavior can be restored by specifying `flush_on_shutdown: true` setting in streaming aggregation config. See more details [here](https://docs.victoriametrics.com/stream-aggregation.html#aggregation-outputs).
* FEATURE: [vmalert](https://docs.victoriametrics.com/vmagent.html): expose ability to set OAuth2 endpoint parameters via the following command-line flags:
-`-datasource.oauth2.endpointParams` for `-datasource.url`
-`-notifier.oauth2.endpointParams` for `-notifier.url`
-`-remoteRead.oauth2.endpointParams` for `-remoteRead.url`
-`-remoteWrite.oauth2.endpointParams` for `-remoteWrite.url`
* FEATURE: [vmauth](https://docs.victoriametrics.com/vmauth.html): add ability to proxy incoming requests to different backends based on the requested host via `src_hosts` option at `url_map`. See [these docs](https://docs.victoriametrics.com/vmauth.html#generic-http-proxy-for-different-backends).
* FEATURE: [vmauth](https://docs.victoriametrics.com/vmauth.html): expose `vmauth_user_request_backend_errors_total` and `vmauth_unauthorized_user_request_backend_errors_total` [metrics](https://docs.victoriametrics.com/vmauth.html#monitoring), which track the number of failed requests because of backend errors. See [this feature request](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/5565).
* FEATURE: [vmauth](https://docs.victoriametrics.com/vmauth.html): add an ability to specify additional labels for [per-user metrics](https://docs.victoriametrics.com/vmauth.html#monitoring) via `metric_labels` section. See [this feature request](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/5565).
* FEATURE: all VictoriaMetrics components: break HTTP client connection if an error occurs after the server at `-httpListenAddr` already sent response status code. Previously such an error couldn't be detected at client side. Now the client will get an error about invalid chunked response. The error message is simultaneously written to the server log and in the last line of the response. This should help detecting errors when migrating data between VictoriaMetrics instances by [vmctl](https://docs.victoriametrics.com/vmctl.html). See [this issue](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/5645).
* FEATURE: all VictoriaMetrics components: add ability to specify arbitrary HTTP headers to send with every request to `-pushmetrics.url`. See [`push metrics` docs](https://docs.victoriametrics.com/#push-metrics).
* FEATURE: all VictoriaMetrics components: add `-metrics.exposeMetadata` command-line flag, which allows displaying `TYPE` and `HELP` metadata at `/metrics` page exposed at `-httpListenAddr`. This may be needed when the `/metrics` page is scraped by collector, which requires the `TYPE` and `HELP` metadata such as [Google Cloud Managed Prometheus](https://cloud.google.com/stackdriver/docs/managed-prometheus/troubleshooting#missing-metric-type).
* FEATURE: all VictoriaMetrics components: add ability to dynamically re-read auth keys and passwords from files and urls when using `file:///path/to/file` or `http://host/path` syntax for the following command-line flags: `-configAuthKey`, `-deleteAuthKey`, `-flagsAuthKey`, `-forceMergeAuthKey`, `-forceFlushAuthKey`, `-httpAuth.password`, `-metricsAuthKey`, `-pprofAuthKey`, `-reloadAuthKey`, `-search.resetCacheAuthKey`, `-snapshotAuthKey`. For example, `-httpAuth.password=file:///path/to/password`. See [these docs](https://docs.victoriametrics.com/#security) for details.
* FEATURE: dashboards/cluster: add panels for detailed visualization of traffic usage between vmstorage, vminsert, vmselect components and their clients. New panels are available in the rows dedicated to specific components.
* FEATURE: dashboards/cluster: update "Slow Queries" panel to show percentage of the slow queries to the total number of read queries served by vmselect. The percentage value should make it more clear for users whether there is a service degradation.
* FEATURE: dashboards/single: change dashboard title from `VictoriaMetrics` to `VictoriaMetrics - single-node`. The new title should provide better understanding of this dashboard purpose.
* FEATURE: [vmctl](https://docs.victoriametrics.com/vmctl.html): rename cmd-line flag `vm-native-disable-retries` to `vm-native-disable-per-metric-migration` to better reflect its meaning.
* FEATURE: [vmctl](https://docs.victoriametrics.com/vmctl.html): add `-vm-native-src-insecure-skip-verify` and `-vm-native-dst-insecure-skip-verify` command-line flags for native protocol. It can be used for skipping TLS certificate verification when connecting to the source or destination addresses.
* FEATURE: [Alerting rules for VictoriaMetrics](https://github.com/VictoriaMetrics/VictoriaMetrics/tree/master/deployment/docker#alerts): add `job` label to `DiskRunsOutOfSpace` alerting rule, so it is easier to understand to which installation the triggered instance belongs.
* FEATURE: `vmstorage`: add tenant identifier for log messages regarding dropping excessive labels due to limits defined by `-maxLabelsPerTimeseries` or `-maxLabelValueLen` command-line flags. Previously, it was hard to understand to which tenant the dropped labels belong.
* FEATURE: [vmui](https://docs.victoriametrics.com/#vmui): add the ability to export and import query reports:
- add a `Query Analyzer` page that allows you to build graphs from `JSON` data containing the results of executing a query request.
- add an `Export query` button to the graph that saves the result of executing the query in `JSON`. See [this pull request](https://github.com/VictoriaMetrics/VictoriaMetrics/pull/5497).
* FEATURE: [vmui](https://docs.victoriametrics.com/#vmui): add `-vmui.defaultTimezone` flag to set a default timezone. See [this issue](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/5375) and [these docs](https://github.com/VictoriaMetrics/VictoriaMetrics/tree/master/app/vmui#timezone-configuration).
* FEATURE: [vmui](https://docs.victoriametrics.com/#vmui): include UTC in the timezone selection dropdown for standardized time referencing. See [this issue](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/5375).
* FEATURE: [vmui](https://docs.victoriametrics.com/#vmui): add the ability to expand/collapse all tracing entries and download tracing data in .json format. See [this issue](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/5677).
* BUGFIX: properly return the list of matching label names and label values from [`/api/v1/labels`](https://docs.victoriametrics.com/url-examples.html#apiv1labels) and [`/api/v1/label/.../values`](https://docs.victoriametrics.com/url-examples.html#apiv1labelvalues) when the database contains more than `-search.maxUniqueTimeseries` unique [time series](https://docs.victoriametrics.com/keyConcepts.html#time-series) on the selected time range. Previously VictoriaMetrics could return `the number of matching timeseries exceeds ...` error in this case. See [this issue](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/5055).
* BUGFIX: properly return errors from [export APIs](https://docs.victoriametrics.com/#how-to-export-time-series). Previously these errors were silently suppressed. See [this pull request](https://github.com/VictoriaMetrics/VictoriaMetrics/pull/5649).
* BUGFIX: [VictoriaMetrics cluster](https://docs.victoriametrics.com/Cluster-VictoriaMetrics.html): properly return full results when `-search.skipSlowReplicas` command-line flag is passed to `vmselect` and when [vmstorage groups](https://docs.victoriametrics.com/Cluster-VictoriaMetrics.html#vmstorage-groups-at-vmselect) are in use. Previously partial results could be returned in this case.
* BUGFIX: `vminsert`: properly accept samples via [OpenTelemetry data ingestion protocol](https://docs.victoriametrics.com/#sending-data-via-opentelemetry) when these samples have no [resource attributes](https://opentelemetry.io/docs/instrumentation/go/resources/). Previously such samples were silently skipped.
* BUGFIX: `vmstorage`: added missing `-inmemoryDataFlushInterval` command-line flag, which was missing in [VictoriaMetrics cluster](https://docs.victoriametrics.com/Cluster-VictoriaMetrics.html) after implementing [this feature](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/3337) in [v1.85.0](https://github.com/VictoriaMetrics/VictoriaMetrics/releases/tag/v1.85.0).
* BUGFIX: `vmstorage`: properly expire `storage/prefetchedMetricIDs` cache. Previously this cache was never expired, so it could grow big under [high churn rate](https://docs.victoriametrics.com/FAQ.html#what-is-high-churn-rate). This could result in increasing CPU load over time.
* BUGFIX: [vmalert](https://docs.victoriametrics.com/vmalert.html): check `-external.url` schema when starting vmalert, must be `http` or `https`. Before, alertmanager could reject alert notifications if `-external.url` contained no or wrong schema.
* BUGFIX: [vmalert](https://docs.victoriametrics.com/vmalert.html): automatically add `exported_` prefix for original evaluation result label if it's conflicted with external or reserved one, previously it was overridden. See [this issue](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/5161).
* BUGFIX: [vmalert](https://docs.victoriametrics.com/vmalert.html): autogenerate `ALERTS_FOR_STATE` time series for alerting rules with `for: 0`. Previously, `ALERTS_FOR_STATE` was generated only for alerts with `for > 0`. The change aligns with Prometheus behavior. See more details in [this issue](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/5648).
* BUGFIX: [vmalert](https://docs.victoriametrics.com/vmalert.html): fix data race during hot-config reload. The result of the race could cause all rules from updated group to fail with `context cancelled` error.
* BUGFIX: [MetricsQL](https://docs.victoriametrics.com/MetricsQL.html): consistently sort results for `q1 or q2` query, so they do not change colors with each refresh in Grafana. See [this issue](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/5393).
* BUGFIX: [MetricsQL](https://docs.victoriametrics.com/MetricsQL.html): properly return results from [bottomk](https://docs.victoriametrics.com/MetricsQL.html#bottomk) and `bottomk_*()` functions when some of these results contain NaN values. See [this issue](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/5506). Thanks to @xiaozongyang for [the fix](https://github.com/VictoriaMetrics/VictoriaMetrics/pull/5509).
* BUGFIX: [MetricsQL](https://docs.victoriametrics.com/MetricsQL.html): properly handle queries, which wrap [rollup functions](https://docs.victoriametrics.com/MetricsQL.html#rollup-functions) with multiple arguments without explicitly specified lookbehind window in square brackets into [aggregate functions](https://docs.victoriametrics.com/MetricsQL.html#aggregate-functions). For example, `sum(quantile_over_time(0.5, process_resident_memory_bytes))` was resulting to `expecting at least 2 args to ...; got 1 args` error. Thanks to @atykhyy for [the pull request](https://github.com/VictoriaMetrics/VictoriaMetrics/pull/5414).
* BUGFIX: [vmctl](https://docs.victoriametrics.com/vmctl.html): retry on import errors in `vm-native` mode. Before, retries happened only on writes into a network connection between source and destination. But errors returned by server after all the data was transmitted were logged, but not retried.
* BUGFIX: [vmagent](https://docs.victoriametrics.com/vmagent.html): properly assume role with [AWS IRSA authorization](https://docs.aws.amazon.com/eks/latest/userguide/iam-roles-for-service-accounts.html). Previously role chaining was not supported. See [this issue](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/3822) for details.
* BUGFIX: [vmagent](https://docs.victoriametrics.com/vmagent.html): exit if there is config syntax error in [`scrape_config_files`](https://docs.victoriametrics.com/vmagent.html#loading-scrape-configs-from-multiple-files) when `-promscrape.config.strictParse=true`. See [this issue](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/5508).
* BUGFIX: [vmagent](https://docs.victoriametrics.com/vmagent.html): properly discover targets for `role: endpoints` and `role: endpointslice` in [kubernetes_sd_configs](https://docs.victoriametrics.com/sd_configs.html#kubernetes_sd_configs). Previously some `endpoints` and `endpointslice` targets could be left undiscovered or some targets could have missing `__meta_*` labels when performing service discovery in busy Kubernetes clusters with large number of pods. See [this pull request](https://github.com/VictoriaMetrics/VictoriaMetrics/pull/5557).
* BUGFIX: [vmagent](https://docs.victoriametrics.com/vmagent.html): respect explicitly set `series_limit: 0` in [scrape_config](https://docs.victoriametrics.com/sd_configs.html#scrape_configs). This allows removing [`series_limit` restriction](https://docs.victoriametrics.com/vmagent.html#cardinality-limiter) on a per-`scrape_config` basis when global limit is set via `-promscrape.seriesLimitPerTarget`. Previously, `0` value was ignored in favor of `-promscrape.seriesLimitPerTarget`.
* BUGFIX: [vmagent](https://docs.victoriametrics.com/vmagent.html): do not discover scrape targets for already terminated pods and containers in [`kubernetes_sd_configs`](https://docs.victoriametrics.com/sd_configs.html#kubernetes_sd_configs). Such pods and containers cannot be scraped and cannot resurrect, so there is no sense in generating scrape targets for them.
* BUGFIX: [vmagent](https://docs.victoriametrics.com/vmagent.html): properly follow redirects to another hostnames when `follow_redirects: true` option is set in [`scrape_configs`](https://docs.victoriametrics.com/sd_configs/#http-api-client-options) while [stream parsing mode](https://docs.victoriametrics.com/vmagent/#stream-parsing-mode) is disabled. See [this issue](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/1945) and [this pull request](https://github.com/VictoriaMetrics/VictoriaMetrics/pull/4931).
* BUGFIX: [vmui](https://docs.victoriametrics.com/#vmui): fix a link for the statistic inaccuracy explanation in the cardinality explorer tool. See [this issue](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/5460).
* BUGFIX: [vmui](https://docs.victoriametrics.com/#vmui): fix the display of autocomplete results and cache the results. See [this issue](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/5472) and [this issue](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/5470).
* BUGFIX: [vmui](https://docs.victoriametrics.com/#vmui): send `step` param for instant queries. The change reverts [this issue](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/3896) due to reasons explained in [this comment](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/3896#issuecomment-1896704401).
* BUGFIX: [vmui](https://docs.victoriametrics.com/#vmui): fix the `Enter` key press issue in the `Query` field when using autocomplete. See [this issue](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/5667).
* BUGFIX: all: fix potential panic during components shutdown when [metrics push](https://docs.victoriametrics.com/#push-metrics) is configured. See [this issue](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/5548). Thanks to @zhdd99 for the [pull request](https://github.com/VictoriaMetrics/VictoriaMetrics/pull/5549).
* BUGFIX: [MetricsQL](https://docs.victoriametrics.com/MetricsQL.html): properly process queries with too big lookbehind window such as `foo[100y]`. Previously, such queries could return empty responses even if `foo` is present in database. See [this issue](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/5553).
* BUGFIX: [MetricsQL](https://docs.victoriametrics.com/MetricsQL.html): properly handle possible negative results caused by float operations precision error in rollup functions like rate() or increase(). See [this issue](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/5571).
* BUGFIX: `vmselect`: vmsingle/vmselect returns http status 429 (TooManyRequests) instead of 503 (ServiceUnavailable) when max concurrent requests limit is reached.
* BUGFIX: `vmselect`: set proper timestamps in [instant query](https://docs.victoriametrics.com/keyconcepts/#instant-query) results if the query contains [rollup functions](https://docs.victoriametrics.com/metricsql/#rollup-functions) with lookbehind windows in square brackets exceeding 3 hours. For example, `sum(avg_over_time(up[24h]))`. This bug has been introduced in [v1.95.0](https://docs.victoriametrics.com/changelog_2023/#v1950). See [this](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/5659) and [this](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/5730) issues.
**v1.93.x is a line of LTS releases (e.g. long-time support). It contains important up-to-date bugfixes.
The v1.93.x line will be supported for at least 12 months since [v1.93.0](https://docs.victoriametrics.com/CHANGELOG.html#v1930) release**
* SECURITY: upgrade Go builder from Go1.21.5 to Go1.21.6. See [the list of issues addressed in Go1.21.6](https://github.com/golang/go/issues?q=milestone%3AGo1.21.6+label%3ACherryPickApproved).
* BUGFIX: `vminsert`: properly accept samples via [OpenTelemetry data ingestion protocol](https://docs.victoriametrics.com/#sending-data-via-opentelemetry) when these samples have no [resource attributes](https://opentelemetry.io/docs/instrumentation/go/resources/). Previously such samples were silently skipped.
* BUGFIX: `vmstorage`: added missing `-inmemoryDataFlushInterval` command-line flag, which was missing in [VictoriaMetrics cluster](https://docs.victoriametrics.com/Cluster-VictoriaMetrics.html) after implementing [this feature](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/3337) in [v1.85.0](https://github.com/VictoriaMetrics/VictoriaMetrics/releases/tag/v1.85.0).
* BUGFIX: `vmstorage`: properly expire `storage/prefetchedMetricIDs` cache. Previously this cache was never expired, so it could grow big under [high churn rate](https://docs.victoriametrics.com/FAQ.html#what-is-high-churn-rate). This could result in increasing CPU load over time.
* BUGFIX: [vmalert](https://docs.victoriametrics.com/vmalert.html): check `-external.url` schema when starting vmalert, must be `http` or `https`. Before, alertmanager could reject alert notifications if `-external.url` contained no or wrong schema.
* BUGFIX: [MetricsQL](https://docs.victoriametrics.com/MetricsQL.html): properly return results from [bottomk](https://docs.victoriametrics.com/MetricsQL.html#bottomk) and `bottomk_*()` functions when some of these results contain NaN values. See [this issue](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/5506). Thanks to @xiaozongyang for [the fix](https://github.com/VictoriaMetrics/VictoriaMetrics/pull/5509).
* BUGFIX: [MetricsQL](https://docs.victoriametrics.com/MetricsQL.html): properly handle queries, which wrap [rollup functions](https://docs.victoriametrics.com/MetricsQL.html#rollup-functions) with multiple arguments without explicitly specified lookbehind window in square brackets into [aggregate functions](https://docs.victoriametrics.com/MetricsQL.html#aggregate-functions). For example, `sum(quantile_over_time(0.5, process_resident_memory_bytes))` was resulting to `expecting at least 2 args to ...; got 1 args` error. Thanks to @atykhyy for [the pull request](https://github.com/VictoriaMetrics/VictoriaMetrics/pull/5414).
* BUGFIX: [vmagent](https://docs.victoriametrics.com/vmagent.html): properly assume role with [AWS IRSA authorization](https://docs.aws.amazon.com/eks/latest/userguide/iam-roles-for-service-accounts.html). Previously role chaining was not supported. See [this issue](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/3822) for details.
* BUGFIX: all: fix potential panic during components shutdown when [metrics push](https://docs.victoriametrics.com/#push-metrics) is configured. See [this issue](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/5548). Thanks to @zhdd99 for the [pull request](https://github.com/VictoriaMetrics/VictoriaMetrics/pull/5549).
* BUGFIX: [vmctl](https://docs.victoriametrics.com/vmctl.html): check for Error field in response from influx client during migration. Before, only network errors were checked. Thanks to @wozz for the [pull request](https://github.com/VictoriaMetrics/VictoriaMetrics/pull/5446).
* BUGFIX: [vmctl](https://docs.victoriametrics.com/vmctl.html): retry on import errors in `vm-native` mode. Before, retries happened only on writes into a network connection between source and destination. But errors returned by server after all the data was transmitted were logged, but not retried.
**v1.87.x is a line of LTS releases (e.g. long-time support). It contains important up-to-date bugfixes.
The v1.87.x line will be supported for at least 12 months since [v1.87.0](https://docs.victoriametrics.com/CHANGELOG.html#v1870) release**
* SECURITY: upgrade Go builder from Go1.21.5 to Go1.21.6. See [the list of issues addressed in Go1.21.6](https://github.com/golang/go/issues?q=milestone%3AGo1.21.6+label%3ACherryPickApproved).
* BUGFIX: `vmstorage`: added missing `-inmemoryDataFlushInterval` command-line flag, which was missing in [VictoriaMetrics cluster](https://docs.victoriametrics.com/Cluster-VictoriaMetrics.html) after implementing [this feature](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/3337) in [v1.85.0](https://github.com/VictoriaMetrics/VictoriaMetrics/releases/tag/v1.85.0).
* BUGFIX: [MetricsQL](https://docs.victoriametrics.com/MetricsQL.html): properly handle queries, which wrap [rollup functions](https://docs.victoriametrics.com/MetricsQL.html#rollup-functions) with multiple arguments without explicitly specified lookbehind window in square brackets into [aggregate functions](https://docs.victoriametrics.com/MetricsQL.html#aggregate-functions). For example, `sum(quantile_over_time(0.5, process_resident_memory_bytes))` was resulting to `expecting at least 2 args to ...; got 1 args` error. Thanks to @atykhyy for [the pull request](https://github.com/VictoriaMetrics/VictoriaMetrics/pull/5414).
* BUGFIX: `vmstorage`: properly expire `storage/prefetchedMetricIDs` cache. Previously this cache was never expired, so it could grow big under [high churn rate](https://docs.victoriametrics.com/FAQ.html#what-is-high-churn-rate). This could result in increasing CPU load over time.
* BUGFIX: [MetricsQL](https://docs.victoriametrics.com/MetricsQL.html): properly return results from [bottomk](https://docs.victoriametrics.com/MetricsQL.html#bottomk) and `bottomk_...` functions when some of these results contain NaN values. See [this issue](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/5506). Thanks to @xiaozongyang for [the fix](https://github.com/VictoriaMetrics/VictoriaMetrics/pull/5509).
* BUGFIX: all: fix potential panic during components shutdown when [metrics push](https://docs.victoriametrics.com/#push-metrics) is configured. See [this issue](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/5548). Thanks to @zhdd99 for the [pull request](https://github.com/VictoriaMetrics/VictoriaMetrics/pull/5549).
