` or `/snapshot/delete_all` in order to free up occupied storage space.
There is no need in synchronizing backups among all the `vmstorage` nodes.
Restoring from backup:
1. Stop `vmstorage` node with `kill -INT`.
2. Restore data from backup using [vmrestore](https://docs.victoriametrics.com/vmrestore.html) into `-storageDataPath` directory.
3. Start `vmstorage` node.
## Downsampling
Downsampling is available in [enterprise version of VictoriaMetrics](https://victoriametrics.com/products/enterprise/). It is configured with `-downsampling.period` command-line flag. The same flag value must be passed to both `vmstorage` and `vmselect` nodes. See [these docs](https://docs.victoriametrics.com/#downsampling) for details.
## Profiling
All the cluster components provide the following handlers for [profiling](https://blog.golang.org/profiling-go-programs):
* `http://vminsert:8480/debug/pprof/heap` for memory profile and `http://vminsert:8480/debug/pprof/profile` for CPU profile
* `http://vmselect:8481/debug/pprof/heap` for memory profile and `http://vmselect:8481/debug/pprof/profile` for CPU profile
* `http://vmstorage:8482/debug/pprof/heap` for memory profile and `http://vmstorage:8482/debug/pprof/profile` for CPU profile
Example command for collecting cpu profile from `vmstorage` (replace `0.0.0.0` with `vmstorage` hostname if needed):
```bash
curl http://0.0.0.0:8482/debug/pprof/profile > cpu.pprof
```
Example command for collecting memory profile from `vminsert` (replace `0.0.0.0` with `vminsert` hostname if needed):
```bash
curl http://0.0.0.0:8480/debug/pprof/heap > mem.pprof
```
## Community and contributions
We are open to third-party pull requests provided they follow the [KISS design principle](https://en.wikipedia.org/wiki/KISS_principle):
- Prefer simple code and architecture.
- Avoid complex abstractions.
- Avoid magic code and fancy algorithms.
- Avoid [big external dependencies](https://medium.com/@valyala/stripping-dependency-bloat-in-victoriametrics-docker-image-983fb5912b0d).
- Minimize the number of moving parts in the distributed system.
- Avoid automated decisions, which may hurt cluster availability, consistency or performance.
Adhering to the `KISS` principle simplifies the resulting code and architecture, so it can be reviewed, understood and verified by many people.
Due to `KISS`, cluster version of VictoriaMetrics has no the following "features" popular in distributed computing world:
- Fragile gossip protocols. See [failed attempt in Thanos](https://github.com/improbable-eng/thanos/blob/030bc345c12c446962225221795f4973848caab5/docs/proposals/completed/201809_gossip-removal.md).
- Hard-to-understand-and-implement-properly [Paxos protocols](https://www.quora.com/In-distributed-systems-what-is-a-simple-explanation-of-the-Paxos-algorithm).
- Complex replication schemes, which may go nuts in unforeseen edge cases. See [replication docs](#replication-and-data-safety) for details.
- Automatic data reshuffling between storage nodes, which may hurt cluster performance and availability.
- Automatic cluster resizing, which may cost you a lot of money if improperly configured.
- Automatic discovering and addition of new nodes in the cluster, which may mix data between dev and prod clusters :)
- Automatic leader election, which may result in split brain disaster on network errors.
## Reporting bugs
Report bugs and propose new features [here](https://github.com/VictoriaMetrics/VictoriaMetrics/issues).
## List of command-line flags
* [List of command-line flags for vminsert](#list-of-command-line-flags-for-vminsert)
* [List of command-line flags for vmselect](#list-of-command-line-flags-for-vmselect)
* [List of command-line flags for vmstorage](#list-of-command-line-flags-for-vmstorage)
### List of command-line flags for vminsert
Below is the output for `/path/to/vminsert -help`:
```
-clusternativeListenAddr string
TCP address to listen for data from other vminsert nodes in multi-level cluster setup. See https://docs.victoriametrics.com/Cluster-VictoriaMetrics.html#multi-level-cluster-setup . Usually :8400 must be set. Doesn't work if empty
-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)
-datadog.maxInsertRequestSize size
The maximum size in bytes of a single DataDog POST request to /api/v1/series
Supports the following optional suffixes for size values: KB, MB, GB, KiB, MiB, GiB (default 67108864)
-disableRerouting
Whether to disable re-routing when some of vmstorage nodes accept incoming data at slower speed compared to other storage nodes. Disabled re-routing limits the ingestion rate by the slowest vmstorage node. On the other side, disabled re-routing minimizes the number of active time series in the cluster during rolling restarts and during spikes in series churn rate. See also -dropSamplesOnOverload (default true)
-dropSamplesOnOverload
Whether to drop incoming samples if the destination vmstorage node is overloaded and/or unavailable. This prioritizes cluster availability over consistency, e.g. the cluster continues accepting all the ingested samples, but some of them may be dropped if vmstorage nodes are temporarily unavailable and/or overloaded
-enableTCP6
Whether to enable IPv6 for listening and dialing. By default only IPv4 TCP and UDP is used
-envflag.enable
Whether to enable reading flags from environment variables additionally to command line. Command line flag values have priority over values from environment vars. Flags are read only from command line if this flag isn't set. See https://docs.victoriametrics.com/#environment-variables for more details
-envflag.prefix string
Prefix for environment variables if -envflag.enable is set
-eula
By specifying this flag, you confirm that you have an enterprise license and accept the EULA https://victoriametrics.com/assets/VM_EULA.pdf
-fs.disableMmap
Whether to use pread() instead of mmap() for reading data files. By default mmap() is used for 64-bit arches and pread() is used for 32-bit arches, since they cannot read data files bigger than 2^32 bytes in memory. mmap() is usually faster for reading small data chunks than pread()
-graphiteListenAddr string
TCP and UDP address to listen for Graphite plaintext data. Usually :2003 must be set. Doesn't work if empty
-graphiteTrimTimestamp duration
Trim timestamps for Graphite data to this duration. Minimum practical duration is 1s. Higher duration (i.e. 1m) may be used for reducing disk space usage for timestamp data (default 1s)
-http.connTimeout duration
Incoming http connections are closed after the configured timeout. This may help to spread the incoming load among a cluster of services behind a load balancer. Please note that the real timeout may be bigger by up to 10% as a protection against the thundering herd problem (default 2m0s)
-http.disableResponseCompression
Disable compression of HTTP responses to save CPU resources. By default compression is enabled to save network bandwidth
-http.idleConnTimeout duration
Timeout for incoming idle http connections (default 1m0s)
-http.maxGracefulShutdownDuration duration
The maximum duration for a graceful shutdown of the HTTP server. A highly loaded server may require increased value for a graceful shutdown (default 7s)
-http.pathPrefix string
An optional prefix to add to all the paths handled by http server. For example, if '-http.pathPrefix=/foo/bar' is set, then all the http requests will be handled on '/foo/bar/*' paths. This may be useful for proxied requests. See https://www.robustperception.io/using-external-urls-and-proxies-with-prometheus
-http.shutdownDelay duration
Optional delay before http server shutdown. During this delay, the server returns non-OK responses from /health page, so load balancers can route new requests to other servers
-httpListenAddr string
Address to listen for http connections (default ":8480")
-import.maxLineLen size
The maximum length in bytes of a single line accepted by /api/v1/import; the line length can be limited with 'max_rows_per_line' query arg passed to /api/v1/export
Supports the following optional suffixes for size values: KB, MB, GB, KiB, MiB, GiB (default 104857600)
-influx.databaseNames array
Comma-separated list of database names to return from /query and /influx/query API. This can be needed for accepting data from Telegraf plugins such as https://github.com/fangli/fluent-plugin-influxdb
Supports an array of values separated by comma or specified via multiple flags.
-influx.maxLineSize size
The maximum size in bytes for a single InfluxDB line during parsing
Supports the following optional suffixes for size values: KB, MB, GB, KiB, MiB, GiB (default 262144)
-influxListenAddr string
TCP and UDP address to listen for InfluxDB line protocol data. Usually :8189 must be set. Doesn't work if empty. This flag isn't needed when ingesting data over HTTP - just send it to http://:8428/write
-influxMeasurementFieldSeparator string
Separator for '{measurement}{separator}{field_name}' metric name when inserted via InfluxDB line protocol (default "_")
-influxSkipMeasurement
Uses '{field_name}' as a metric name while ignoring '{measurement}' and '-influxMeasurementFieldSeparator'
-influxSkipSingleField
Uses '{measurement}' instead of '{measurement}{separator}{field_name}' for metic name if InfluxDB line contains only a single field
-influxTrimTimestamp duration
Trim timestamps for InfluxDB line protocol 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)
-insert.maxQueueDuration duration
The maximum duration for waiting in the queue for insert requests due to -maxConcurrentInserts (default 1m0s)
-loggerDisableTimestamps
Whether to disable writing timestamps in logs
-loggerErrorsPerSecondLimit int
Per-second limit on the number of ERROR messages. If more than the given number of errors are emitted per second, the remaining errors are suppressed. Zero values disable the rate limit
-loggerFormat string
Format for logs. Possible values: default, json (default "default")
-loggerLevel string
Minimum level of errors to log. Possible values: INFO, WARN, ERROR, FATAL, PANIC (default "INFO")
-loggerOutput string
Output for the logs. Supported values: stderr, stdout (default "stderr")
-loggerTimezone string
Timezone to use for timestamps in logs. Timezone must be a valid IANA Time Zone. For example: America/New_York, Europe/Berlin, Etc/GMT+3 or Local (default "UTC")
-loggerWarnsPerSecondLimit int
Per-second limit on the number of WARN messages. If more than the given number of warns are emitted per second, then the remaining warns are suppressed. Zero values disable the rate limit
-maxConcurrentInserts int
The maximum number of concurrent inserts. Default value should work for most cases, since it minimizes the overhead for concurrent inserts. This option is tigthly coupled with -insert.maxQueueDuration (default 16)
-maxInsertRequestSize size
The maximum size in bytes of a single Prometheus remote_write API request
Supports the following optional suffixes for size values: KB, MB, GB, KiB, MiB, GiB (default 33554432)
-maxLabelValueLen int
The maximum length of label values in the accepted time series. Longer label values are truncated. In this case the vm_too_long_label_values_total metric at /metrics page is incremented (default 16384)
-maxLabelsPerTimeseries int
The maximum number of labels accepted per time series. Superfluous labels are dropped. In this case the vm_metrics_with_dropped_labels_total metric at /metrics page is incremented (default 30)
-memory.allowedBytes size
Allowed size of system memory VictoriaMetrics caches may occupy. This option overrides -memory.allowedPercent if set to a non-zero value. Too low a value may increase the cache miss rate usually resulting in higher CPU and disk IO usage. Too high a value may evict too much data from OS page cache resulting in higher disk IO usage
Supports the following optional suffixes for size values: KB, MB, GB, KiB, MiB, GiB (default 0)
-memory.allowedPercent float
Allowed percent of system memory VictoriaMetrics caches may occupy. See also -memory.allowedBytes. Too low a value may increase cache miss rate usually resulting in higher CPU and disk IO usage. Too high a value may evict too much data from OS page cache which will result in higher disk IO usage (default 60)
-opentsdbHTTPListenAddr string
TCP address to listen for OpentTSDB HTTP put requests. Usually :4242 must be set. Doesn't work if empty
-opentsdbListenAddr string
TCP and UDP address to listen for OpentTSDB metrics. Telnet put messages and HTTP /api/put messages are simultaneously served on TCP port. Usually :4242 must be set. Doesn't work if empty
-opentsdbTrimTimestamp duration
Trim timestamps for OpenTSDB 'telnet put' data to this duration. Minimum practical duration is 1s. Higher duration (i.e. 1m) may be used for reducing disk space usage for timestamp data (default 1s)
-opentsdbhttp.maxInsertRequestSize size
The maximum size of OpenTSDB HTTP put request
Supports the following optional suffixes for size values: KB, MB, GB, KiB, MiB, GiB (default 33554432)
-opentsdbhttpTrimTimestamp duration
Trim timestamps for OpenTSDB HTTP 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)
-relabelConfig string
Optional path to a file with relabeling rules, which are applied to all the ingested metrics. The path can point either to local file or to http url. See https://docs.victoriametrics.com/#relabeling for details. The config is reloaded on SIGHUP signal
-relabelDebug
Whether to log metrics before and after relabeling with -relabelConfig. If the -relabelDebug is enabled, then the metrics aren't sent to storage. This is useful for debugging the relabeling configs
-replicationFactor int
Replication factor for the ingested data, i.e. how many copies to make among distinct -storageNode instances. Note that vmselect must run with -dedup.minScrapeInterval=1ms for data de-duplication when replicationFactor is greater than 1. Higher values for -dedup.minScrapeInterval at vmselect is OK (default 1)
-rpc.disableCompression
Whether to disable compression of RPC traffic. This reduces CPU usage at the cost of higher network bandwidth usage
-sortLabels
Whether to sort labels for incoming samples before writing them to storage. This may be needed for reducing memory usage at storage when the order of labels in incoming samples is random. For example, if m{k1="v1",k2="v2"} may be sent as m{k2="v2",k1="v1"}. Enabled sorting for labels can slow down ingestion performance a bit
-storageNode array
Comma-separated addresses of vmstorage nodes; usage: -storageNode=vmstorage-host1,...,vmstorage-hostN
Supports an array of values separated by comma or specified via multiple flags.
-tls
Whether to enable TLS (aka HTTPS) for incoming requests. -tlsCertFile and -tlsKeyFile must be set if -tls is set
-tlsCertFile string
Path to file with TLS certificate. Used only if -tls is set. Prefer ECDSA certs instead of RSA certs as RSA certs are slower. The provided certificate file is automatically re-read every second, so it can be dynamically updated
-tlsKeyFile string
Path to file with TLS key. Used only if -tls is set. The provided key file is automatically re-read every second, so it can be dynamically updated
-version
Show VictoriaMetrics version
```
### List of command-line flags for vmselect
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
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
-downsampling.period array
Comma-separated downsampling periods in the format 'offset:period'. For example, '30d:10m' instructs to leave a single sample per 10 minutes for samples older than 30 days. See https://docs.victoriametrics.com/#downsampling for details
Supports an array of values separated by comma or specified via multiple flags.
-enableTCP6
Whether to enable IPv6 for listening and dialing. By default only IPv4 TCP and UDP is used
-envflag.enable
Whether to enable reading flags from environment variables additionally to command line. Command line flag values have priority over values from environment vars. Flags are read only from command line if this flag isn't set. See https://docs.victoriametrics.com/#environment-variables for more details
-envflag.prefix string
Prefix for environment variables if -envflag.enable is set
-eula
By specifying this flag, you confirm that you have an enterprise license and accept the EULA https://victoriametrics.com/assets/VM_EULA.pdf
-fs.disableMmap
Whether to use pread() instead of mmap() for reading data files. By default mmap() is used for 64-bit arches and pread() is used for 32-bit arches, since they cannot read data files bigger than 2^32 bytes in memory. mmap() is usually faster for reading small data chunks than pread()
-graphiteTrimTimestamp duration
Trim timestamps for Graphite data to this duration. Minimum practical duration is 1s. Higher duration (i.e. 1m) may be used for reducing disk space usage for timestamp data (default 1s)
-http.connTimeout duration
Incoming http connections are closed after the configured timeout. This may help to spread the incoming load among a cluster of services behind a load balancer. Please note that the real timeout may be bigger by up to 10% as a protection against the thundering herd problem (default 2m0s)
-http.disableResponseCompression
Disable compression of HTTP responses to save CPU resources. By default compression is enabled to save network bandwidth
-http.idleConnTimeout duration
Timeout for incoming idle http connections (default 1m0s)
-http.maxGracefulShutdownDuration duration
The maximum duration for a graceful shutdown of the HTTP server. A highly loaded server may require increased value for a graceful shutdown (default 7s)
-http.pathPrefix string
An optional prefix to add to all the paths handled by http server. For example, if '-http.pathPrefix=/foo/bar' is set, then all the http requests will be handled on '/foo/bar/*' paths. This may be useful for proxied requests. See https://www.robustperception.io/using-external-urls-and-proxies-with-prometheus
-http.shutdownDelay duration
Optional delay before http server shutdown. During this delay, the server returns non-OK responses from /health page, so load balancers can route new requests to other servers
-httpListenAddr string
Address to listen for http connections (default ":8481")
-loggerDisableTimestamps
Whether to disable writing timestamps in logs
-loggerErrorsPerSecondLimit int
Per-second limit on the number of ERROR messages. If more than the given number of errors are emitted per second, the remaining errors are suppressed. Zero values disable the rate limit
-loggerFormat string
Format for logs. Possible values: default, json (default "default")
-loggerLevel string
Minimum level of errors to log. Possible values: INFO, WARN, ERROR, FATAL, PANIC (default "INFO")
-loggerOutput string
Output for the logs. Supported values: stderr, stdout (default "stderr")
-loggerTimezone string
Timezone to use for timestamps in logs. Timezone must be a valid IANA Time Zone. For example: America/New_York, Europe/Berlin, Etc/GMT+3 or Local (default "UTC")
-loggerWarnsPerSecondLimit int
Per-second limit on the number of WARN messages. If more than the given number of warns are emitted per second, then the remaining warns are suppressed. Zero values disable the rate limit
-memory.allowedBytes size
Allowed size of system memory VictoriaMetrics caches may occupy. This option overrides -memory.allowedPercent if set to a non-zero value. Too low a value may increase the cache miss rate usually resulting in higher CPU and disk IO usage. Too high a value may evict too much data from OS page cache resulting in higher disk IO usage
Supports the following optional suffixes for size values: KB, MB, GB, KiB, MiB, GiB (default 0)
-memory.allowedPercent float
Allowed percent of system memory VictoriaMetrics caches may occupy. See also -memory.allowedBytes. Too low a value may increase cache miss rate usually resulting in higher CPU and disk IO usage. Too high a value may evict too much data from OS page cache which will result in higher disk IO usage (default 60)
-replicationFactor int
How many copies of every time series is available on vmstorage nodes. See -replicationFactor command-line flag for vminsert nodes (default 1)
-search.cacheTimestampOffset duration
The maximum duration since the current time for response data, which is always queried from the original raw data, without using the response cache. Increase this value if you see gaps in responses due to time synchronization issues between VictoriaMetrics and data sources (default 5m0s)
-search.denyPartialResponse
Whether to deny partial responses if a part of -storageNode instances fail to perform queries; this trades availability over consistency; see also -search.maxQueryDuration
-search.disableCache
Whether to disable response caching. This may be useful during data backfilling
-search.graphiteMaxPointsPerSeries int
The maximum number of points per series Graphite render API can return (default 1000000)
-search.graphiteStorageStep duration
The interval between datapoints stored in the database. It is used at Graphite Render API handler for normalizing the interval between datapoints in case it isn't normalized. It can be overriden by sending 'storage_step' query arg to /render API or by sending the desired interval via 'Storage-Step' http header during querying /render API (default 10s)
-search.latencyOffset duration
The time when data points become visible in query results after the collection. Too small value can result in incomplete last points for query results (default 30s)
-search.logSlowQueryDuration duration
Log queries with execution time exceeding this value. Zero disables slow query logging (default 5s)
-search.maxConcurrentRequests int
The maximum number of concurrent search requests. It shouldn't be high, since a single request can saturate all the CPU cores. See also -search.maxQueueDuration (default 8)
-search.maxExportDuration duration
The maximum duration for /api/v1/export call (default 720h0m0s)
-search.maxLookback duration
Synonym to -search.lookback-delta from Prometheus. The value is dynamically detected from interval between time series datapoints if not set. It can be overridden on per-query basis via max_lookback arg. See also '-search.maxStalenessInterval' flag, which has the same meaining due to historical reasons
-search.maxPointsPerTimeseries int
The maximum points per a single timeseries returned from /api/v1/query_range. This option doesn't limit the number of scanned raw samples in the database. The main purpose of this option is to limit the number of per-series points returned to graphing UI such as Grafana. There is no sense in setting this limit to values bigger than the horizontal resolution of the graph (default 30000)
-search.maxQueryDuration duration
The maximum duration for query execution (default 30s)
-search.maxQueryLen size
The maximum search query length in bytes
Supports the following optional suffixes for size values: KB, MB, GB, KiB, MiB, GiB (default 16384)
-search.maxQueueDuration duration
The maximum time the request waits for execution when -search.maxConcurrentRequests limit is reached; see also -search.maxQueryDuration (default 10s)
-search.maxSamplesPerQuery int
The maximum number of raw samples a single query can process across all time series. This protects from heavy queries, which select unexpectedly high number of raw samples. See also -search.maxSamplesPerSeries (default 1000000000)
-search.maxSamplesPerSeries int
The maximum number of raw samples a single query can scan per each time series. See also -search.maxSamplesPerQuery (default 30000000)
-search.maxStalenessInterval duration
The maximum interval for staleness calculations. By default it is automatically calculated from the median interval between samples. This flag could be useful for tuning Prometheus data model closer to Influx-style data model. See https://prometheus.io/docs/prometheus/latest/querying/basics/#staleness for details. See also '-search.maxLookback' flag, which has the same meaning due to historical reasons
-search.maxStatusRequestDuration duration
The maximum duration for /api/v1/status/* requests (default 5m0s)
-search.maxStepForPointsAdjustment duration
The maximum step when /api/v1/query_range handler adjusts points with timestamps closer than -search.latencyOffset to the current time. The adjustment is needed because such points may contain incomplete data (default 1m0s)
-search.minStalenessInterval duration
The minimum interval for staleness calculations. This flag could be useful for removing gaps on graphs generated from time series with irregular intervals between samples. See also '-search.maxStalenessInterval'
-search.noStaleMarkers
Set this flag to true if the database doesn't contain Prometheus stale markers, so there is no need in spending additional CPU time on its handling. Staleness markers may exist only in data obtained from Prometheus scrape targets
-search.queryStats.lastQueriesCount int
Query stats for /api/v1/status/top_queries is tracked on this number of last queries. Zero value disables query stats tracking (default 20000)
-search.queryStats.minQueryDuration duration
The minimum duration for queries to track in query stats at /api/v1/status/top_queries. Queries with lower duration are ignored in query stats (default 1ms)
-search.resetCacheAuthKey string
Optional authKey for resetting rollup cache via /internal/resetRollupResultCache call
-search.treatDotsAsIsInRegexps
Whether to treat dots as is in regexp label filters used in queries. For example, foo{bar=~"a.b.c"} will be automatically converted to foo{bar=~"a\\.b\\.c"}, i.e. all the dots in regexp filters will be automatically escaped in order to match only dot char instead of matching any char. Dots in ".+", ".*" and ".{n}" regexps aren't escaped. This option is DEPRECATED in favor of {__graphite__="a.*.c"} syntax for selecting metrics matching the given Graphite metrics filter
-selectNode array
Comma-serparated addresses of vmselect nodes; usage: -selectNode=vmselect-host1,...,vmselect-hostN
Supports an array of values separated by comma or specified via multiple flags.
-storageNode array
Comma-separated addresses of vmstorage nodes; usage: -storageNode=vmstorage-host1,...,vmstorage-hostN
Supports an array of values separated by comma or specified via multiple flags.
-tls
Whether to enable TLS (aka HTTPS) for incoming requests. -tlsCertFile and -tlsKeyFile must be set if -tls is set
-tlsCertFile string
Path to file with TLS certificate. Used only if -tls is set. Prefer ECDSA certs instead of RSA certs as RSA certs are slower. The provided certificate file is automatically re-read every second, so it can be dynamically updated
-tlsKeyFile string
Path to file with TLS key. Used only if -tls is set. The provided key file is automatically re-read every second, so it can be dynamically updated
-version
Show VictoriaMetrics version
```
### List of command-line flags for vmstorage
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
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
-downsampling.period array
Comma-separated downsampling periods in the format 'offset:period'. For example, '30d:10m' instructs to leave a single sample per 10 minutes for samples older than 30 days. See https://docs.victoriametrics.com/#downsampling for details
Supports an array of values separated by comma or specified via multiple flags.
-enableTCP6
Whether to enable IPv6 for listening and dialing. By default only IPv4 TCP and UDP is used
-envflag.enable
Whether to enable reading flags from environment variables additionally to command line. Command line flag values have priority over values from environment vars. Flags are read only from command line if this flag isn't set. See https://docs.victoriametrics.com/#environment-variables for more details
-envflag.prefix string
Prefix for environment variables if -envflag.enable is set
-eula
By specifying this flag, you confirm that you have an enterprise license and accept the EULA https://victoriametrics.com/assets/VM_EULA.pdf
-finalMergeDelay duration
The delay before starting final merge for per-month partition after no new data is ingested into it. Final merge may require additional disk IO and CPU resources. Final merge may increase query speed and reduce disk space usage in some cases. Zero value disables final merge
-forceFlushAuthKey string
authKey, which must be passed in query string to /internal/force_flush pages
-forceMergeAuthKey string
authKey, which must be passed in query string to /internal/force_merge pages
-fs.disableMmap
Whether to use pread() instead of mmap() for reading data files. By default mmap() is used for 64-bit arches and pread() is used for 32-bit arches, since they cannot read data files bigger than 2^32 bytes in memory. mmap() is usually faster for reading small data chunks than pread()
-http.connTimeout duration
Incoming http connections are closed after the configured timeout. This may help to spread the incoming load among a cluster of services behind a load balancer. Please note that the real timeout may be bigger by up to 10% as a protection against the thundering herd problem (default 2m0s)
-http.disableResponseCompression
Disable compression of HTTP responses to save CPU resources. By default compression is enabled to save network bandwidth
-http.idleConnTimeout duration
Timeout for incoming idle http connections (default 1m0s)
-http.maxGracefulShutdownDuration duration
The maximum duration for a graceful shutdown of the HTTP server. A highly loaded server may require increased value for a graceful shutdown (default 7s)
-http.pathPrefix string
An optional prefix to add to all the paths handled by http server. For example, if '-http.pathPrefix=/foo/bar' is set, then all the http requests will be handled on '/foo/bar/*' paths. This may be useful for proxied requests. See https://www.robustperception.io/using-external-urls-and-proxies-with-prometheus
-http.shutdownDelay duration
Optional delay before http server shutdown. During this delay, the server returns non-OK responses from /health page, so load balancers can route new requests to other servers
-httpListenAddr string
Address to listen for http connections (default ":8482")
-logNewSeries
Whether to log new series. This option is for debug purposes only. It can lead to performance issues when big number of new series are ingested into VictoriaMetrics
-loggerDisableTimestamps
Whether to disable writing timestamps in logs
-loggerErrorsPerSecondLimit int
Per-second limit on the number of ERROR messages. If more than the given number of errors are emitted per second, the remaining errors are suppressed. Zero values disable the rate limit
-loggerFormat string
Format for logs. Possible values: default, json (default "default")
-loggerLevel string
Minimum level of errors to log. Possible values: INFO, WARN, ERROR, FATAL, PANIC (default "INFO")
-loggerOutput string
Output for the logs. Supported values: stderr, stdout (default "stderr")
-loggerTimezone string
Timezone to use for timestamps in logs. Timezone must be a valid IANA Time Zone. For example: America/New_York, Europe/Berlin, Etc/GMT+3 or Local (default "UTC")
-loggerWarnsPerSecondLimit int
Per-second limit on the number of WARN messages. If more than the given number of warns are emitted per second, then the remaining warns are suppressed. Zero values disable the rate limit
-memory.allowedBytes size
Allowed size of system memory VictoriaMetrics caches may occupy. This option overrides -memory.allowedPercent if set to a non-zero value. Too low a value may increase the cache miss rate usually resulting in higher CPU and disk IO usage. Too high a value may evict too much data from OS page cache resulting in higher disk IO usage
Supports the following optional suffixes for size values: KB, MB, GB, KiB, MiB, GiB (default 0)
-memory.allowedPercent float
Allowed percent of system memory VictoriaMetrics caches may occupy. See also -memory.allowedBytes. Too low a value may increase cache miss rate usually resulting in higher CPU and disk IO usage. Too high a value may evict too much data from OS page cache which will result in higher disk IO usage (default 60)
-precisionBits int
The number of precision bits to store per each value. Lower precision bits improves data compression at the cost of precision loss (default 64)
-retentionPeriod value
Data with timestamps outside the retentionPeriod is automatically deleted
The following optional suffixes are supported: h (hour), d (day), w (week), y (year). If suffix isn't set, then the duration is counted in months (default 1)
-rpc.disableCompression
Disable compression of RPC traffic. This reduces CPU usage at the cost of higher network bandwidth usage
-search.maxTagKeys int
The maximum number of tag keys returned per search (default 100000)
-search.maxTagValueSuffixesPerSearch int
The maximum number of tag value suffixes returned from /metrics/find (default 100000)
-search.maxTagValues int
The maximum number of tag values returned per search (default 100000)
-search.maxUniqueTimeseries int
The maximum number of unique time series a single query can process. This allows protecting against heavy queries, which select unexpectedly high number of series. See also -search.maxSamplesPerQuery and -search.maxSamplesPerSeries (default 300000)
-smallMergeConcurrency int
The maximum number of CPU cores to use for small merges. Default value is used if set to 0
-snapshotAuthKey string
authKey, which must be passed in query string to /snapshot* pages
-storage.maxDailySeries int
The maximum number of unique series can be added to the storage during the last 24 hours. Excess series are logged and dropped. This can be useful for limiting series churn rate. See also -storage.maxHourlySeries
-storage.maxHourlySeries int
The maximum number of unique series can be added to the storage during the last hour. Excess series are logged and dropped. This can be useful for limiting series cardinality. See also -storage.maxDailySeries
-storage.minFreeDiskSpaceBytes size
The minimum free disk space at -storageDataPath after which the storage stops accepting new data
Supports the following optional suffixes for size values: KB, MB, GB, KiB, MiB, GiB (default 10000000)
-storageDataPath string
Path to storage data (default "vmstorage-data")
-tls
Whether to enable TLS (aka HTTPS) for incoming requests. -tlsCertFile and -tlsKeyFile must be set if -tls is set
-tlsCertFile string
Path to file with TLS certificate. Used only if -tls is set. Prefer ECDSA certs instead of RSA certs as RSA certs are slower. The provided certificate file is automatically re-read every second, so it can be dynamically updated
-tlsKeyFile string
Path to file with TLS key. Used only if -tls is set. The provided key file is automatically re-read every second, so it can be dynamically updated
-version
Show VictoriaMetrics version
-vminsertAddr string
TCP address to accept connections from vminsert services (default ":8400")
-vmselectAddr string
TCP address to accept connections from vmselect services (default ":8401")
```
## VictoriaMetrics Logo
[Zip](VM_logo.zip) contains three folders with different image orientation (main color and inverted version).
Files included in each folder:
* 2 JPEG Preview files
* 2 PNG Preview files with transparent background
* 2 EPS Adobe Illustrator EPS10 files
### Logo Usage Guidelines
#### Font used:
* Lato Black
* Lato Regular
#### Color Palette:
* HEX [#110f0f](https://www.color-hex.com/color/110f0f)
* HEX [#ffffff](https://www.color-hex.com/color/ffffff)
### We kindly ask:
- Please don't use any other font instead of suggested.
- There should be sufficient clear space around the logo.
- Do not change spacing, alignment, or relative locations of the design elements.
- Do not change the proportions of any of the design elements or the design itself. You may resize as needed but must retain all proportions.
VictoriaMetrics is a fast, cost-effective and scalable time series database. It can be used as a long-term remote storage for Prometheus.
It is recommended using [single-node version](https://github.com/VictoriaMetrics/VictoriaMetrics) instead of cluster version
for ingestion rates lower than a million of data points per second.
Single-node version [scales perfectly](https://medium.com/@valyala/measuring-vertical-scalability-for-time-series-databases-in-google-cloud-92550d78d8ae)
with the number of CPU cores, RAM and available storage space.
Single-node version is easier to configure and operate comparing to cluster version, so think twice before sticking to cluster version.
Join [our Slack](https://slack.victoriametrics.com/) or [contact us](mailto:info@victoriametrics.com) with consulting and support questions.
## Prominent features
- Supports all the features of [single-node version](https://github.com/VictoriaMetrics/VictoriaMetrics).
- Performance and capacity scales horizontally. See [these docs for details](#cluster-resizing-and-scalability).
- Supports multiple independent namespaces for time series data (aka multi-tenancy). See [these docs for details](#multitenancy).
- Supports replication. See [these docs for details](#replication-and-data-safety).
## Architecture overview
VictoriaMetrics cluster consists of the following services:
- `vmstorage` - stores the raw data and returns the queried data on the given time range for the given label filters
- `vminsert` - accepts the ingested data and spreads it among `vmstorage` nodes according to consistent hashing over metric name and all its labels
- `vmselect` - performs incoming queries by fetching the needed data from all the configured `vmstorage` nodes
Each service may scale independently and may run on the most suitable hardware.
`vmstorage` nodes don't know about each other, don't communicate with each other and don't share any data.
This is [shared nothing architecture](https://en.wikipedia.org/wiki/Shared-nothing_architecture).
It increases cluster availability, simplifies cluster maintenance and cluster scaling.