docs: fix links to FAQ.md entries after they have been changed in ccf04239e6

README.md

@@ -1067,7 +1067,7 @@ with scrape intervals exceeding `5m`.
 
 VictoriaMetrics uses lower amounts of CPU, RAM and storage space on production workloads compared to competing solutions (Prometheus, Thanos, Cortex, TimescaleDB, InfluxDB, QuestDB, M3DB) according to [our case studies](https://docs.victoriametrics.com/CaseStudies.html).
 
-VictoriaMetrics capacity scales linearly with the available resources. The needed amounts of CPU and RAM highly depends on the workload - the number of [active time series](https://docs.victoriametrics.com/FAQ.html#what-is-active-time-series), series [churn rate](https://docs.victoriametrics.com/FAQ.html#what-is-high-churn-rate), query types, query qps, etc. It is recommended setting up a test VictoriaMetrics for your production workload and iteratively scaling CPU and RAM resources until it becomes stable according to [troubleshooting docs](#troubleshooting). A single-node VictoriaMetrics works perfectly with the following production workload according to [our case studies](https://docs.victoriametrics.com/CaseStudies.html):
+VictoriaMetrics capacity scales linearly with the available resources. The needed amounts of CPU and RAM highly depends on the workload - the number of [active time series](https://docs.victoriametrics.com/FAQ.html#what-is-an-active-time-series), series [churn rate](https://docs.victoriametrics.com/FAQ.html#what-is-high-churn-rate), query types, query qps, etc. It is recommended setting up a test VictoriaMetrics for your production workload and iteratively scaling CPU and RAM resources until it becomes stable according to [troubleshooting docs](#troubleshooting). A single-node VictoriaMetrics works perfectly with the following production workload according to [our case studies](https://docs.victoriametrics.com/CaseStudies.html):
 
 * Ingestion rate: 1.5+ million samples per second
 * Active time series: 50+ million
@@ -1272,7 +1272,7 @@ It is recommended setting up alerts in [vmalert](https://docs.victoriametrics.co
 The most interesting metrics are:
 
 * `vm_cache_entries{type="storage/hour_metric_ids"}` - the number of time series with new data points during the last hour
-  aka [active time series](https://docs.victoriametrics.com/FAQ.html#what-is-active-time-series).
+  aka [active time series](https://docs.victoriametrics.com/FAQ.html#what-is-an-active-time-series).
 * `increase(vm_new_timeseries_created_total[1h])` - time series [churn rate](https://docs.victoriametrics.com/FAQ.html#what-is-high-churn-rate) during the previous hour.
 * `sum(vm_rows{type=~"storage/.*"})` - total number of `(timestamp, value)` data points in the database.
 * `sum(rate(vm_rows_inserted_total[5m]))` - ingestion rate, i.e. how many samples are inserted int the database per second.
@@ -1280,10 +1280,10 @@ The most interesting metrics are:
 * `sum(vm_data_size_bytes)` - the total size of data on disk.
 * `increase(vm_slow_row_inserts_total[5m])` - the number of slow inserts during the last 5 minutes.
   If this number remains high during extended periods of time, then it is likely more RAM is needed for optimal handling
-  of the current number of [active time series](https://docs.victoriametrics.com/FAQ.html#what-is-active-time-series).
+  of the current number of [active time series](https://docs.victoriametrics.com/FAQ.html#what-is-an-active-time-series).
 * `increase(vm_slow_metric_name_loads_total[5m])` - the number of slow loads of metric names during the last 5 minutes.
   If this number remains high during extended periods of time, then it is likely more RAM is needed for optimal handling
-  of the current number of [active time series](https://docs.victoriametrics.com/FAQ.html#what-is-active-time-series).
+  of the current number of [active time series](https://docs.victoriametrics.com/FAQ.html#what-is-an-active-time-series).
 
 VictoriaMetrics also exposes currently running queries with their execution times at `/api/v1/status/active_queries` page.
 
@@ -1303,7 +1303,7 @@ VictoriaMetrics returns TSDB stats at `/api/v1/status/tsdb` page in the way simi
 
 By default VictoriaMetrics doesn't limit the number of stored time series. The limit can be enforced by setting the following command-line flags:
 
-* `-storage.maxHourlySeries` - limits the number of time series that can be added during the last hour. Useful for limiting the number of [active time series](https://docs.victoriametrics.com/FAQ.html#what-is-active-time-series).
+* `-storage.maxHourlySeries` - limits the number of time series that can be added during the last hour. Useful for limiting the number of [active time series](https://docs.victoriametrics.com/FAQ.html#what-is-an-active-time-series).
 * `-storage.maxDailySeries` - limits the number of time series that can be added during the last day. Useful for limiting daily [churn rate](https://docs.victoriametrics.com/FAQ.html#what-is-high-churn-rate).
 
 Both limits can be set simultaneously. If any of these limits is reached, then incoming samples for new time series are dropped. A sample of dropped series is put in the log with `WARNING` level.
@@ -1347,7 +1347,7 @@ See also more advanced [cardinality limiter in vmagent](https://docs.victoriamet
     See [this article for technical details](https://valyala.medium.com/wal-usage-looks-broken-in-modern-time-series-databases-b62a627ab704).
 
 * If VictoriaMetrics works slowly and eats more than a CPU core per 100K ingested data points per second,
-  then it is likely you have too many [active time series](https://docs.victoriametrics.com/FAQ.html#what-is-active-time-series) for the current amount of RAM.
+  then it is likely you have too many [active time series](https://docs.victoriametrics.com/FAQ.html#what-is-an-active-time-series) for the current amount of RAM.
   VictoriaMetrics [exposes](#monitoring) `vm_slow_*` metrics such as `vm_slow_row_inserts_total` and `vm_slow_metric_name_loads_total`, which could be used
   as an indicator of low amounts of RAM. It is recommended increasing the amount of RAM on the node with VictoriaMetrics in order to improve
   ingestion and query performance in this case.

docs/Cluster-VictoriaMetrics.md

@@ -307,7 +307,7 @@ Data replication can be used for increasing storage durability. See [these docs]
 
 VictoriaMetrics uses lower amounts of CPU, RAM and storage space on production workloads compared to competing solutions (Prometheus, Thanos, Cortex, TimescaleDB, InfluxDB, QuestDB, M3DB) according to [our case studies](https://docs.victoriametrics.com/CaseStudies.html).
 
-Each node type - `vminsert`, `vmselect` and `vmstorage` - can run on the most suitable hardware. Cluster capacity scales linearly with the available resources. The needed amounts of CPU and RAM per each node type highly depends on the workload - the number of [active time series](https://docs.victoriametrics.com/FAQ.html#what-is-active-time-series), [series churn rate](https://docs.victoriametrics.com/FAQ.html#what-is-high-churn-rate), query types, query qps, etc. It is recommended setting up a test VictoriaMetrics cluster for your production workload and iteratively scaling per-node resources and the number of nodes per node type until the cluster becomes stable. It is recommended setting up [monitoring for the cluster](#monitoring). It helps determining bottlenecks in cluster setup. It is also recommended following [the troubleshooting docs](https://docs.victoriametrics.com/#troubleshooting).
+Each node type - `vminsert`, `vmselect` and `vmstorage` - can run on the most suitable hardware. Cluster capacity scales linearly with the available resources. The needed amounts of CPU and RAM per each node type highly depends on the workload - the number of [active time series](https://docs.victoriametrics.com/FAQ.html#what-is-an-active-time-series), [series churn rate](https://docs.victoriametrics.com/FAQ.html#what-is-high-churn-rate), query types, query qps, etc. It is recommended setting up a test VictoriaMetrics cluster for your production workload and iteratively scaling per-node resources and the number of nodes per node type until the cluster becomes stable. It is recommended setting up [monitoring for the cluster](#monitoring). It helps determining bottlenecks in cluster setup. It is also recommended following [the troubleshooting docs](https://docs.victoriametrics.com/#troubleshooting).
 
 The needed storage space for the given retention (the retention is set via `-retentionPeriod` command-line flag at `vmstorage`) can be extrapolated from disk space usage in a test run. For example, if the storage space usage is 10GB after a day-long test run on a production workload, then it will need at least `10GB*100=1TB` of disk space for `-retentionPeriod=100d` (100-days retention period). Storage space usage can be monitored with [the official Grafana dashboard for VictoriaMetrics cluster](#monitoring).
 
@@ -321,7 +321,7 @@ It is recommended leaving the following amounts of spare resources:
 Some capacity planning tips for VictoriaMetrics cluster:
 
 * The [replication](#replication-and-data-safety) increases the amounts of needed resources for the cluster by up to `N` times where `N` is replication factor.
-* Cluster capacity for [active time series](https://docs.victoriametrics.com/FAQ.html#what-is-active-time-series) can be increased by adding more `vmstorage` nodes and/or by increasing RAM and CPU resources per each `vmstorage` node.
+* Cluster capacity for [active time series](https://docs.victoriametrics.com/FAQ.html#what-is-an-active-time-series) can be increased by adding more `vmstorage` nodes and/or by increasing RAM and CPU resources per each `vmstorage` node.
 * Query latency can be reduced by increasing the number of `vmstorage` nodes and/or by increasing RAM and CPU resources per each `vmselect` node.
 * The total number of CPU cores needed for all the `vminsert` nodes can be calculated from the ingestion rate: `CPUs = ingestion_rate / 100K`.
 * The `-rpc.disableCompression` command-line flag at `vminsert` nodes can increase ingestion capacity at the cost of higher network bandwidth usage between `vminsert` and `vmstorage`.

docs/FAQ.md

@@ -312,12 +312,12 @@ The solution against high churn rate is to identify and eliminate labels with fr
 
 ## What is high cardinality?
 
-High cardinality usually means a high number of [active time series](#what-is-active-time-series). High cardinality may lead to high memory usage and/or to a high percentage of [slow inserts](#what-is-slow-insert). The source of high cardinality is usually a label with a large number of unique values, which presents a big share of the ingested time series. The solution is to identify and remove the source of high cardinality with the help of [/api/v1/status/tsdb](https://docs.victoriametrics.com/#tsdb-stats).
+High cardinality usually means a high number of [active time series](#what-is-an-active-time-series). High cardinality may lead to high memory usage and/or to a high percentage of [slow inserts](#what-is-a-slow-insert). The source of high cardinality is usually a label with a large number of unique values, which presents a big share of the ingested time series. The solution is to identify and remove the source of high cardinality with the help of [/api/v1/status/tsdb](https://docs.victoriametrics.com/#tsdb-stats).
 
 
 ## What is a slow insert?
 
-VictoriaMetrics maintains in-memory cache for mapping of [active time series](#what-is-active-time-series) into internal series ids. The cache size depends on the available memory for VictoriaMetrics in the host system. If the information about all the active time series doesn't fit the cache, then VictoriaMetrics needs to read and unpack the information from disk on every incoming sample for time series missing in the cache. This operation is much slower than the cache lookup, so such an insert is named a `slow insert`. A high percentage of slow inserts on the [official dashboard for VictoriaMetrics](https://docs.victoriametrics.com/#monitoring) indicates a memory shortage for the current number of [active time series](#what-is-active-time-series). Such a condition usually leads to a significant slowdown for data ingestion and to significantly increased disk IO and CPU usage. The solution is to add more memory or to reduce the number of [active time series](#what-is-active-time-series). The `/api/v1/status/tsdb` page can be helpful for locating the source of high number of active time seriess – see [these docs](https://docs.victoriametrics.com/#tsdb-stats).
+VictoriaMetrics maintains in-memory cache for mapping of [active time series](#what-is-an-active-time-series) into internal series ids. The cache size depends on the available memory for VictoriaMetrics in the host system. If the information about all the active time series doesn't fit the cache, then VictoriaMetrics needs to read and unpack the information from disk on every incoming sample for time series missing in the cache. This operation is much slower than the cache lookup, so such an insert is named a `slow insert`. A high percentage of slow inserts on the [official dashboard for VictoriaMetrics](https://docs.victoriametrics.com/#monitoring) indicates a memory shortage for the current number of [active time series](#what-is-an-active-time-series). Such a condition usually leads to a significant slowdown for data ingestion and to significantly increased disk IO and CPU usage. The solution is to add more memory or to reduce the number of [active time series](#what-is-an-active-time-series). The `/api/v1/status/tsdb` page can be helpful for locating the source of high number of active time seriess – see [these docs](https://docs.victoriametrics.com/#tsdb-stats).
 
 
 ## How to optimize MetricsQL query?
@@ -359,4 +359,4 @@ The query engine may behave differently for some functions. Please see [this art
 
 ## If downsampling and deduplication are enabled how will this work?
 
-[Deduplication](https://docs.victoriametrics.com/#deduplication) is a special case of zero-offset [downsampling](https://docs.victoriametrics.com/#downsampling). So, if both downsampling and deduplication are enabled, then deduplication is replaced by zero-offset downsampling
+[Deduplication](https://docs.victoriametrics.com/#deduplication) is a special case of zero-offset [downsampling](https://docs.victoriametrics.com/#downsampling). So, if both downsampling and deduplication are enabled, then deduplication is replaced by zero-offset downsampling

docs/README.md

@@ -1067,7 +1067,7 @@ with scrape intervals exceeding `5m`.
 
 VictoriaMetrics uses lower amounts of CPU, RAM and storage space on production workloads compared to competing solutions (Prometheus, Thanos, Cortex, TimescaleDB, InfluxDB, QuestDB, M3DB) according to [our case studies](https://docs.victoriametrics.com/CaseStudies.html).
 
-VictoriaMetrics capacity scales linearly with the available resources. The needed amounts of CPU and RAM highly depends on the workload - the number of [active time series](https://docs.victoriametrics.com/FAQ.html#what-is-active-time-series), series [churn rate](https://docs.victoriametrics.com/FAQ.html#what-is-high-churn-rate), query types, query qps, etc. It is recommended setting up a test VictoriaMetrics for your production workload and iteratively scaling CPU and RAM resources until it becomes stable according to [troubleshooting docs](#troubleshooting). A single-node VictoriaMetrics works perfectly with the following production workload according to [our case studies](https://docs.victoriametrics.com/CaseStudies.html):
+VictoriaMetrics capacity scales linearly with the available resources. The needed amounts of CPU and RAM highly depends on the workload - the number of [active time series](https://docs.victoriametrics.com/FAQ.html#what-is-an-active-time-series), series [churn rate](https://docs.victoriametrics.com/FAQ.html#what-is-high-churn-rate), query types, query qps, etc. It is recommended setting up a test VictoriaMetrics for your production workload and iteratively scaling CPU and RAM resources until it becomes stable according to [troubleshooting docs](#troubleshooting). A single-node VictoriaMetrics works perfectly with the following production workload according to [our case studies](https://docs.victoriametrics.com/CaseStudies.html):
 
 * Ingestion rate: 1.5+ million samples per second
 * Active time series: 50+ million
@@ -1272,7 +1272,7 @@ It is recommended setting up alerts in [vmalert](https://docs.victoriametrics.co
 The most interesting metrics are:
 
 * `vm_cache_entries{type="storage/hour_metric_ids"}` - the number of time series with new data points during the last hour
-  aka [active time series](https://docs.victoriametrics.com/FAQ.html#what-is-active-time-series).
+  aka [active time series](https://docs.victoriametrics.com/FAQ.html#what-is-an-active-time-series).
 * `increase(vm_new_timeseries_created_total[1h])` - time series [churn rate](https://docs.victoriametrics.com/FAQ.html#what-is-high-churn-rate) during the previous hour.
 * `sum(vm_rows{type=~"storage/.*"})` - total number of `(timestamp, value)` data points in the database.
 * `sum(rate(vm_rows_inserted_total[5m]))` - ingestion rate, i.e. how many samples are inserted int the database per second.
@@ -1280,10 +1280,10 @@ The most interesting metrics are:
 * `sum(vm_data_size_bytes)` - the total size of data on disk.
 * `increase(vm_slow_row_inserts_total[5m])` - the number of slow inserts during the last 5 minutes.
   If this number remains high during extended periods of time, then it is likely more RAM is needed for optimal handling
-  of the current number of [active time series](https://docs.victoriametrics.com/FAQ.html#what-is-active-time-series).
+  of the current number of [active time series](https://docs.victoriametrics.com/FAQ.html#what-is-an-active-time-series).
 * `increase(vm_slow_metric_name_loads_total[5m])` - the number of slow loads of metric names during the last 5 minutes.
   If this number remains high during extended periods of time, then it is likely more RAM is needed for optimal handling
-  of the current number of [active time series](https://docs.victoriametrics.com/FAQ.html#what-is-active-time-series).
+  of the current number of [active time series](https://docs.victoriametrics.com/FAQ.html#what-is-an-active-time-series).
 
 VictoriaMetrics also exposes currently running queries with their execution times at `/api/v1/status/active_queries` page.
 
@@ -1303,7 +1303,7 @@ VictoriaMetrics returns TSDB stats at `/api/v1/status/tsdb` page in the way simi
 
 By default VictoriaMetrics doesn't limit the number of stored time series. The limit can be enforced by setting the following command-line flags:
 
-* `-storage.maxHourlySeries` - limits the number of time series that can be added during the last hour. Useful for limiting the number of [active time series](https://docs.victoriametrics.com/FAQ.html#what-is-active-time-series).
+* `-storage.maxHourlySeries` - limits the number of time series that can be added during the last hour. Useful for limiting the number of [active time series](https://docs.victoriametrics.com/FAQ.html#what-is-an-active-time-series).
 * `-storage.maxDailySeries` - limits the number of time series that can be added during the last day. Useful for limiting daily [churn rate](https://docs.victoriametrics.com/FAQ.html#what-is-high-churn-rate).
 
 Both limits can be set simultaneously. If any of these limits is reached, then incoming samples for new time series are dropped. A sample of dropped series is put in the log with `WARNING` level.
@@ -1347,7 +1347,7 @@ See also more advanced [cardinality limiter in vmagent](https://docs.victoriamet
     See [this article for technical details](https://valyala.medium.com/wal-usage-looks-broken-in-modern-time-series-databases-b62a627ab704).
 
 * If VictoriaMetrics works slowly and eats more than a CPU core per 100K ingested data points per second,
-  then it is likely you have too many [active time series](https://docs.victoriametrics.com/FAQ.html#what-is-active-time-series) for the current amount of RAM.
+  then it is likely you have too many [active time series](https://docs.victoriametrics.com/FAQ.html#what-is-an-active-time-series) for the current amount of RAM.
   VictoriaMetrics [exposes](#monitoring) `vm_slow_*` metrics such as `vm_slow_row_inserts_total` and `vm_slow_metric_name_loads_total`, which could be used
   as an indicator of low amounts of RAM. It is recommended increasing the amount of RAM on the node with VictoriaMetrics in order to improve
   ingestion and query performance in this case.

docs/Single-server-VictoriaMetrics.md

@@ -1071,7 +1071,7 @@ with scrape intervals exceeding `5m`.
 
 VictoriaMetrics uses lower amounts of CPU, RAM and storage space on production workloads compared to competing solutions (Prometheus, Thanos, Cortex, TimescaleDB, InfluxDB, QuestDB, M3DB) according to [our case studies](https://docs.victoriametrics.com/CaseStudies.html).
 
-VictoriaMetrics capacity scales linearly with the available resources. The needed amounts of CPU and RAM highly depends on the workload - the number of [active time series](https://docs.victoriametrics.com/FAQ.html#what-is-active-time-series), series [churn rate](https://docs.victoriametrics.com/FAQ.html#what-is-high-churn-rate), query types, query qps, etc. It is recommended setting up a test VictoriaMetrics for your production workload and iteratively scaling CPU and RAM resources until it becomes stable according to [troubleshooting docs](#troubleshooting). A single-node VictoriaMetrics works perfectly with the following production workload according to [our case studies](https://docs.victoriametrics.com/CaseStudies.html):
+VictoriaMetrics capacity scales linearly with the available resources. The needed amounts of CPU and RAM highly depends on the workload - the number of [active time series](https://docs.victoriametrics.com/FAQ.html#what-is-an-active-time-series), series [churn rate](https://docs.victoriametrics.com/FAQ.html#what-is-high-churn-rate), query types, query qps, etc. It is recommended setting up a test VictoriaMetrics for your production workload and iteratively scaling CPU and RAM resources until it becomes stable according to [troubleshooting docs](#troubleshooting). A single-node VictoriaMetrics works perfectly with the following production workload according to [our case studies](https://docs.victoriametrics.com/CaseStudies.html):
 
 * Ingestion rate: 1.5+ million samples per second
 * Active time series: 50+ million
@@ -1276,7 +1276,7 @@ It is recommended setting up alerts in [vmalert](https://docs.victoriametrics.co
 The most interesting metrics are:
 
 * `vm_cache_entries{type="storage/hour_metric_ids"}` - the number of time series with new data points during the last hour
-  aka [active time series](https://docs.victoriametrics.com/FAQ.html#what-is-active-time-series).
+  aka [active time series](https://docs.victoriametrics.com/FAQ.html#what-is-an-active-time-series).
 * `increase(vm_new_timeseries_created_total[1h])` - time series [churn rate](https://docs.victoriametrics.com/FAQ.html#what-is-high-churn-rate) during the previous hour.
 * `sum(vm_rows{type=~"storage/.*"})` - total number of `(timestamp, value)` data points in the database.
 * `sum(rate(vm_rows_inserted_total[5m]))` - ingestion rate, i.e. how many samples are inserted int the database per second.
@@ -1284,10 +1284,10 @@ The most interesting metrics are:
 * `sum(vm_data_size_bytes)` - the total size of data on disk.
 * `increase(vm_slow_row_inserts_total[5m])` - the number of slow inserts during the last 5 minutes.
   If this number remains high during extended periods of time, then it is likely more RAM is needed for optimal handling
-  of the current number of [active time series](https://docs.victoriametrics.com/FAQ.html#what-is-active-time-series).
+  of the current number of [active time series](https://docs.victoriametrics.com/FAQ.html#what-is-an-active-time-series).
 * `increase(vm_slow_metric_name_loads_total[5m])` - the number of slow loads of metric names during the last 5 minutes.
   If this number remains high during extended periods of time, then it is likely more RAM is needed for optimal handling
-  of the current number of [active time series](https://docs.victoriametrics.com/FAQ.html#what-is-active-time-series).
+  of the current number of [active time series](https://docs.victoriametrics.com/FAQ.html#what-is-an-active-time-series).
 
 VictoriaMetrics also exposes currently running queries with their execution times at `/api/v1/status/active_queries` page.
 
@@ -1307,7 +1307,7 @@ VictoriaMetrics returns TSDB stats at `/api/v1/status/tsdb` page in the way simi
 
 By default VictoriaMetrics doesn't limit the number of stored time series. The limit can be enforced by setting the following command-line flags:
 
-* `-storage.maxHourlySeries` - limits the number of time series that can be added during the last hour. Useful for limiting the number of [active time series](https://docs.victoriametrics.com/FAQ.html#what-is-active-time-series).
+* `-storage.maxHourlySeries` - limits the number of time series that can be added during the last hour. Useful for limiting the number of [active time series](https://docs.victoriametrics.com/FAQ.html#what-is-an-active-time-series).
 * `-storage.maxDailySeries` - limits the number of time series that can be added during the last day. Useful for limiting daily [churn rate](https://docs.victoriametrics.com/FAQ.html#what-is-high-churn-rate).
 
 Both limits can be set simultaneously. If any of these limits is reached, then incoming samples for new time series are dropped. A sample of dropped series is put in the log with `WARNING` level.
@@ -1351,7 +1351,7 @@ See also more advanced [cardinality limiter in vmagent](https://docs.victoriamet
     See [this article for technical details](https://valyala.medium.com/wal-usage-looks-broken-in-modern-time-series-databases-b62a627ab704).
 
 * If VictoriaMetrics works slowly and eats more than a CPU core per 100K ingested data points per second,
-  then it is likely you have too many [active time series](https://docs.victoriametrics.com/FAQ.html#what-is-active-time-series) for the current amount of RAM.
+  then it is likely you have too many [active time series](https://docs.victoriametrics.com/FAQ.html#what-is-an-active-time-series) for the current amount of RAM.
   VictoriaMetrics [exposes](#monitoring) `vm_slow_*` metrics such as `vm_slow_row_inserts_total` and `vm_slow_metric_name_loads_total`, which could be used
   as an indicator of low amounts of RAM. It is recommended increasing the amount of RAM on the node with VictoriaMetrics in order to improve
   ingestion and query performance in this case.