app/{vmselect,vmstorage}: clarify the description for -dedup.minScrapeInterval command-line flag

Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/1426

README.md

@@ -1602,7 +1602,7 @@ Pass `-help` to VictoriaMetrics in order to see the list of supported command-li
   -csvTrimTimestamp duration
     	Trim timestamps when importing csv data to this duration. Minimum practical duration is 1ms. Higher duration (i.e. 1s) may be used for reducing disk space usage for timestamp data (default 1ms)
   -dedup.minScrapeInterval duration
-    	Remove superflouos samples from time series if they are located closer to each other than this duration. This may be useful for reducing overhead when multiple identically configured Prometheus instances write data to the same VictoriaMetrics. Deduplication is disabled if the -dedup.minScrapeInterval is 0
+    	Leave only the first sample in every time series per each discrete interval equal to -dedup.minScrapeInterval > 0. See https://docs.victoriametrics.com/#deduplication for details
   -deleteAuthKey string
     	authKey for metrics' deletion via /api/v1/admin/tsdb/delete_series and /tags/delSeries
   -denyQueriesOutsideRetention
@@ -1730,7 +1730,7 @@ Pass `-help` to VictoriaMetrics in order to see the list of supported command-li
   -promscrape.consulSDCheckInterval duration
     	Interval for checking for changes in Consul. This works only if consul_sd_configs is configured in '-promscrape.config' file. See https://prometheus.io/docs/prometheus/latest/configuration/configuration/#consul_sd_config for details (default 30s)
   -promscrape.digitaloceanSDCheckInterval duration
-        Interval for checking for changes in digital ocean. This works only if digitalocean_sd_configs is configured in '-promscrape.config' file. See https://prometheus.io/docs/prometheus/latest/configuration/configuration/#digitalocean_sd_config for details (default 1m0s)    	
+    	Interval for checking for changes in digital ocean. This works only if digitalocean_sd_configs is configured in '-promscrape.config' file. See https://prometheus.io/docs/prometheus/latest/configuration/configuration/#digitalocean_sd_config for details (default 1m0s)
   -promscrape.disableCompression
     	Whether to disable sending 'Accept-Encoding: gzip' request headers to all the scrape targets. This may reduce CPU usage on scrape targets at the cost of higher network bandwidth utilization. It is possible to set 'disable_compression: true' individually per each 'scrape_config' section in '-promscrape.config' for fine grained control
   -promscrape.disableKeepAlive
@@ -1741,6 +1741,8 @@ Pass `-help` to VictoriaMetrics in order to see the list of supported command-li
     	The maximum duration for waiting to perform API requests if more than -promscrape.discovery.concurrency requests are simultaneously performed (default 1m0s)
   -promscrape.dnsSDCheckInterval duration
     	Interval for checking for changes in dns. This works only if dns_sd_configs is configured in '-promscrape.config' file. See https://prometheus.io/docs/prometheus/latest/configuration/configuration/#dns_sd_config for details (default 30s)
+  -promscrape.dockerSDCheckInterval duration
+    	Interval for checking for changes in docker. This works only if docker_sd_configs is configured in '-promscrape.config' file. See https://prometheus.io/docs/prometheus/latest/configuration/configuration/#docker_sd_config for details (default 30s)
   -promscrape.dockerswarmSDCheckInterval duration
     	Interval for checking for changes in dockerswarm. This works only if dockerswarm_sd_configs is configured in '-promscrape.config' file. See https://prometheus.io/docs/prometheus/latest/configuration/configuration/#dockerswarm_sd_config for details (default 30s)
   -promscrape.dropOriginalLabels
@@ -1754,7 +1756,7 @@ Pass `-help` to VictoriaMetrics in order to see the list of supported command-li
   -promscrape.gceSDCheckInterval duration
     	Interval for checking for changes in gce. This works only if gce_sd_configs is configured in '-promscrape.config' file. See https://prometheus.io/docs/prometheus/latest/configuration/configuration/#gce_sd_config for details (default 1m0s)
   -promscrape.httpSDCheckInterval duration
-        Interval for checking for changes in http service discovery. This works only if http_sd_configs is configured in '-promscrape.config' file. See https://prometheus.io/docs/prometheus/latest/configuration/configuration/#http_sd_config for details (default 1m0s)    	
+    	Interval for checking for changes in http endpoint service discovery. This works only if http_sd_configs is configured in '-promscrape.config' file. See https://prometheus.io/docs/prometheus/latest/configuration/configuration/#http_sd_config for details (default 1m0s)
   -promscrape.kubernetes.apiServerTimeout duration
     	How frequently to reload the full state from Kuberntes API server (default 30m0s)
   -promscrape.kubernetesSDCheckInterval duration

app/victoria-metrics/main.go

@@ -24,9 +24,8 @@ import (
 
 var (
 	httpListenAddr    = flag.String("httpListenAddr", ":8428", "TCP address to listen for http connections")
-	minScrapeInterval = flag.Duration("dedup.minScrapeInterval", 0, "Remove superflouos samples from time series if they are located closer to each other than this duration. "+
+	minScrapeInterval = flag.Duration("dedup.minScrapeInterval", 0, "Leave only the first sample in every time series per each discrete interval "+
-		"This may be useful for reducing overhead when multiple identically configured Prometheus instances write data to the same VictoriaMetrics. "+
+		"equal to -dedup.minScrapeInterval > 0. See https://docs.victoriametrics.com/#deduplication for details")
-		"Deduplication is disabled if the -dedup.minScrapeInterval is 0")
 	dryRun = flag.Bool("dryRun", false, "Whether to check only -promscrape.config and then exit. "+
 		"Unknown config entries are allowed in -promscrape.config by default. This can be changed with -promscrape.config.strictParse")
 )

docs/Cluster-VictoriaMetrics.md

@@ -597,7 +597,7 @@ Below is the output for `/path/to/vmselect -help`:
   -cacheDataPath string
     	Path to directory for cache files. Cache isn't saved if empty
   -dedup.minScrapeInterval duration
-    	Remove superflouos samples from time series if they are located closer to each other than this duration. This may be useful for reducing overhead when multiple identically configured Prometheus instances write data to the same VictoriaMetrics. Deduplication is disabled if the -dedup.minScrapeInterval is 0
+    	Leave only the first sample in every time series per each discrete interval equal to -dedup.minScrapeInterval > 0. See https://docs.victoriametrics.com/#deduplication for details
   -enableTCP6
     	Whether to enable IPv6 for listening and dialing. By default only IPv4 TCP and UDP is used
   -envflag.enable
@@ -708,7 +708,7 @@ Below is the output for `/path/to/vmstorage -help`:
   -bigMergeConcurrency int
     	The maximum number of CPU cores to use for big merges. Default value is used if set to 0
   -dedup.minScrapeInterval duration
-    	Remove superflouos samples from time series if they are located closer to each other than this duration. This may be useful for reducing overhead when multiple identically configured Prometheus instances write data to the same VictoriaMetrics. Deduplication is disabled if the -dedup.minScrapeInterval is 0
+    	Leave only the first sample in every time series per each discrete interval equal to -dedup.minScrapeInterval > 0. See https://docs.victoriametrics.com/#deduplication for details
   -denyQueriesOutsideRetention
     	Whether to deny queries outside of the configured -retentionPeriod. When set, then /api/v1/query_range would return '503 Service Unavailable' error for queries with 'from' value outside -retentionPeriod. This may be useful when multiple data sources with distinct retentions are hidden behind query-tee
   -enableTCP6

docs/Single-server-VictoriaMetrics.md

@@ -1606,7 +1606,7 @@ Pass `-help` to VictoriaMetrics in order to see the list of supported command-li
   -csvTrimTimestamp duration
     	Trim timestamps when importing csv data to this duration. Minimum practical duration is 1ms. Higher duration (i.e. 1s) may be used for reducing disk space usage for timestamp data (default 1ms)
   -dedup.minScrapeInterval duration
-    	Remove superflouos samples from time series if they are located closer to each other than this duration. This may be useful for reducing overhead when multiple identically configured Prometheus instances write data to the same VictoriaMetrics. Deduplication is disabled if the -dedup.minScrapeInterval is 0
+    	Leave only the first sample in every time series per each discrete interval equal to -dedup.minScrapeInterval > 0. See https://docs.victoriametrics.com/#deduplication for details
   -deleteAuthKey string
     	authKey for metrics' deletion via /api/v1/admin/tsdb/delete_series and /tags/delSeries
   -denyQueriesOutsideRetention
@@ -1734,7 +1734,7 @@ Pass `-help` to VictoriaMetrics in order to see the list of supported command-li
   -promscrape.consulSDCheckInterval duration
     	Interval for checking for changes in Consul. This works only if consul_sd_configs is configured in '-promscrape.config' file. See https://prometheus.io/docs/prometheus/latest/configuration/configuration/#consul_sd_config for details (default 30s)
   -promscrape.digitaloceanSDCheckInterval duration
-        Interval for checking for changes in digital ocean. This works only if digitalocean_sd_configs is configured in '-promscrape.config' file. See https://prometheus.io/docs/prometheus/latest/configuration/configuration/#digitalocean_sd_config for details (default 1m0s)    	
+    	Interval for checking for changes in digital ocean. This works only if digitalocean_sd_configs is configured in '-promscrape.config' file. See https://prometheus.io/docs/prometheus/latest/configuration/configuration/#digitalocean_sd_config for details (default 1m0s)
   -promscrape.disableCompression
     	Whether to disable sending 'Accept-Encoding: gzip' request headers to all the scrape targets. This may reduce CPU usage on scrape targets at the cost of higher network bandwidth utilization. It is possible to set 'disable_compression: true' individually per each 'scrape_config' section in '-promscrape.config' for fine grained control
   -promscrape.disableKeepAlive
@@ -1745,6 +1745,8 @@ Pass `-help` to VictoriaMetrics in order to see the list of supported command-li
     	The maximum duration for waiting to perform API requests if more than -promscrape.discovery.concurrency requests are simultaneously performed (default 1m0s)
   -promscrape.dnsSDCheckInterval duration
     	Interval for checking for changes in dns. This works only if dns_sd_configs is configured in '-promscrape.config' file. See https://prometheus.io/docs/prometheus/latest/configuration/configuration/#dns_sd_config for details (default 30s)
+  -promscrape.dockerSDCheckInterval duration
+    	Interval for checking for changes in docker. This works only if docker_sd_configs is configured in '-promscrape.config' file. See https://prometheus.io/docs/prometheus/latest/configuration/configuration/#docker_sd_config for details (default 30s)
   -promscrape.dockerswarmSDCheckInterval duration
     	Interval for checking for changes in dockerswarm. This works only if dockerswarm_sd_configs is configured in '-promscrape.config' file. See https://prometheus.io/docs/prometheus/latest/configuration/configuration/#dockerswarm_sd_config for details (default 30s)
   -promscrape.dropOriginalLabels
@@ -1758,7 +1760,7 @@ Pass `-help` to VictoriaMetrics in order to see the list of supported command-li
   -promscrape.gceSDCheckInterval duration
     	Interval for checking for changes in gce. This works only if gce_sd_configs is configured in '-promscrape.config' file. See https://prometheus.io/docs/prometheus/latest/configuration/configuration/#gce_sd_config for details (default 1m0s)
   -promscrape.httpSDCheckInterval duration
-        Interval for checking for changes in http service discovery. This works only if http_sd_configs is configured in '-promscrape.config' file. See https://prometheus.io/docs/prometheus/latest/configuration/configuration/#http_sd_config for details (default 1m0s)    	
+    	Interval for checking for changes in http endpoint service discovery. This works only if http_sd_configs is configured in '-promscrape.config' file. See https://prometheus.io/docs/prometheus/latest/configuration/configuration/#http_sd_config for details (default 1m0s)
   -promscrape.kubernetes.apiServerTimeout duration
     	How frequently to reload the full state from Kuberntes API server (default 30m0s)
   -promscrape.kubernetesSDCheckInterval duration