diff --git a/content/v2.0/reference/glossary.md b/content/v2.0/reference/glossary.md new file mode 100644 index 000000000..68d667cd1 --- /dev/null +++ b/content/v2.0/reference/glossary.md @@ -0,0 +1,793 @@ +--- +title: Glossary +description: > + Terms related to InfluxData products and platforms. +weight: 6 +menu: + v2_0_ref: + name: Glossary +v2.0/tags: [glossary] +--- + +[A](#a) | [B](#b) | [C](#c) | [D](#d) | [E](#e) | [F](#f) |[G](#g) | [H](#h) | [I](#i) | [J](#j) | [K](#k) | [L](#l) | [M](#m) | [N](#n) | [O](#o) | [P](#p) | [Q](#q) | [R](#r) | [S](#s) | [T](#t) | [U](#u) | [V](#v) | [W](#w) | [X](#x) | [Y](#y) | [Z](#z) + +## A + +### agent + +Core part of Telegraf that gathers metrics from the declared input plugins and sends metrics to the declared output plugins, based on the plugins enabled by the given configuration. + +Related entries: [input plugin](#input-plugin), [output plugin](#output-plugin) + +### aggregator plugin + +Receives metrics from input plugins, creates aggregate metrics, and then passes aggregate metrics to configured output plugins. + +Related entries: [input plugin](#input-plugin), [output plugin](#output-plugin), [processor plugin](#processor-plugin) + +### aggregation + +A function that returns an aggregated value across a set of points. +For a list of available aggregation functions, see [Flux built-in aggregate functions](https://v2.docs.influxdata.com/v2.0/reference/flux/functions/built-in/transformations/aggregates/). + +Related entries: [function](#function), [selector](#selector), [transformation](#transformation) + +## B + + + +### batch + +A collection of points in line protocol format, separated by newlines (`0x0A`). +Submitting a batch of points to the database using a single HTTP request to the write endpoints drastically increases performance by reducing the HTTP overhead. +InfluxData typically recommends batch sizes of 5,000-10,000 points. In some use cases, performance may improve with significantly smaller or larger batches. + +Related entries: [line protocol](/v2.0/reference/line-protocol/), [point](#point) + +### batch size + +The Telegraf agent sends metrics to output plugins in batches, not individually. +The batch size controls the size of each write batch that Telegraf sends to the output plugins. + +Related entries: [output plugin](#output-plugin) + + + +### collection interval + +The default global interval for collecting data from each input plugin. +The collection interval can be overridden by each individual input plugin's configuration. + +Related entries: [input plugin](#input-plugin) + +### collection jitter + +Collection jitter is used to prevent every input plugin from collecting metrics simultaneously, which can have a measurable effect on the system. +Each collection interval, every input plugin will sleep for a random time between zero and the collection jitter before collecting the metrics. + +Related entries: [collection interval](#collection-interval), [input plugin](#input-plugin) + +### column + +### comment + +### common log format (CLF) + +### continuous query (CQ) + +An InfluxQL query that runs automatically and periodically within a database. +Continuous queries require a function in the `SELECT` clause and must include a `GROUP BY time()` clause. +See [Continuous Queries](/influxdb/v1.7/query_language/continuous_queries/). + +Related entries: [function](#function) + +## D + +### daemon + +### dashboard + +### Data Explorer + +### data model + +### data node + +A node that runs the data service. + +For high availability, installations must have at least two data nodes. +The number of data nodes in your cluster must be the same as your highest +replication factor. +Any replication factor greater than two gives you additional fault tolerance and +query capacity in the cluster. + +Data node sizes will depend on your needs. The Amazon EC2 m4.large or m4.xlarge are good starting points. + +Related entries: [data service](#data-service), [replication factor](#replication-factor) + +### data service + +Stores time series data and handles writes and queries. + +Related entries: [data node](#data-node) + +### data type + +### database + +A logical container for users, retention policies, continuous queries, and time series data. + +Related entries: [continuous query](#continuous-query-cq), [retention policy](#retention-policy-rp), [user](#user) + +### date-time + +### downsample + +### duration + +The attribute of the retention policy that determines how long InfluxDB stores data. +Data older than the duration are automatically dropped from the database. + + +Related entries: [retention policy](#retention-policy-rp) + + + +## E + +### event + +Measurements gathered at irregular time intervals. + + + +## F + +### field + +The key-value pair in InfluxDB's data structure that records metadata and the actual data value. +Fields are required in InfluxDB's data structure and they are not indexed - queries on field values scan all points that match the specified time range and, as a result, are not performant relative to tags. + +*Query tip:* Compare fields to tags; tags are indexed. + +Related entries: [field key](#field-key), [field set](#field-set), [field value](#field-value), [tag](#tag) + +### field key + +The key part of the key-value pair that makes up a field. +Field keys are strings and they store metadata. + +Related entries: [field](#field), [field set](#field-set), [field value](#field-value), [tag key](#tag-key) + +### field set + +The collection of field keys and field values on a point. + +Related entries: [field](#field), [field key](#field-key), [field value](#field-value), [point](#point) + +### field value + +The value part of the key-value pair that makes up a field. +Field values are the actual data; they can be strings, floats, integers, or booleans. +A field value is always associated with a timestamp. + +Field values are not indexed - queries on field values scan all points that match the specified time range and, as a result, are not performant. + +*Query tip:* Compare field values to tag values; tag values are indexed. + +Related entries: [field](#field), [field key](#field-key), [field set](#field-set), [tag value](#tag-value), [timestamp](#timestamp) + +### file block + +### float + +### flush interval + +The global interval for flushing data from each output plugin to its destination. +This value should not be set lower than the collection interval. + +Related entries: [collection interval](#collection-interval), [flush jitter](#flush-jitter), [output plugin](#output-plugin) + +### flush jitter + +Flush jitter is used to prevent every output plugin from sending writes simultaneously, which can overwhelm some data sinks. +Each flush interval, every output plugin will sleep for a random time between zero and the flush jitter before emitting metrics. +This helps smooth out write spikes when running a large number of Telegraf instances. + +Related entries: [flush interval](#flush-interval), [output plugin](#output-plugin) + +### Flux + +### function + +InfluxQL aggregations, selectors, and transformations. +See [InfluxQL Functions](/influxdb/v1.7/query_language/functions/) for a complete list of InfluxQL functions. + +Related entries: [aggregation](/influxdb/v1.7/concepts/glossary/#aggregation), [selector](/influxdb/v1.7/concepts/glossary/#selector), [transformation](/influxdb/v1.7/concepts/glossary/#transformation) + +### function block + +## G + +### gauge + +### graph + +### gzip + +- compression +- file (`.gz`) + +## H + +### Hinted Handoff (HH) + +### historgram + +## I + +### identifier + +Tokens that refer to continuous query names, database names, field keys, +measurement names, retention policy names, subscription names, tag keys, and +user names. +See [Query Language Specification](/influxdb/v1.7/query_language/spec/#identifiers). + +Related entries: +[database](/influxdb/v1.7/concepts/glossary/#database), +[field key](/influxdb/v1.7/concepts/glossary/#field-key), +[measurement](/influxdb/v1.7/concepts/glossary/#measurement), +[retention policy](/influxdb/v1.7/concepts/glossary/#retention-policy-rp), +[tag key](/influxdb/v1.7/concepts/glossary/#tag-key), +[user](/influxdb/v1.7/concepts/glossary/#user) + +### implicit block + +### influx + +### influxd + +### InfluxDB + +### InfluxDB UI + +### InfluxQL + +### input plugin + +Input plugins actively gather metrics and deliver them to the core agent, where aggregator, processor, and output plugins can operate on the metrics. +In order to activate an input plugin, it needs to be enabled and configured in Telegraf's configuration file. + +Related entries: [aggregator plugin](/telegraf/v1.10/concepts/glossary/#aggregator-plugin), [collection interval](/telegraf/v1.10/concepts/glossary/#collection-interval), [output plugin](/telegraf/v1.10/concepts/glossary/#output-plugin), [processor plugin](/telegraf/v1.10/concepts/glossary/#processor-plugin) + +### instance + +### int (data type) + +## J + +### JWT + +### Jaeger + +### Java Web Tokens + +### join + +## K + +### Kapacitor + +### keyword + +## L + +### literal + +### load balancing + +### Log Viewer + +### logging + +### Line Protocol (LP) + +The text based format for writing points to InfluxDB. See [Line Protocol](/influxdb/v1.7/write_protocols/). + +## M + +### measurement + +The part of InfluxDB's structure that describes the data stored in the associated fields. +Measurements are strings. + +Related entries: [field](/influxdb/v1.7/concepts/glossary/#field), [series](/influxdb/v1.7/concepts/glossary/#series) + +### member + +### meta node - e + +A node that runs the meta service. + +For high availability, installations must have three meta nodes. +Meta nodes can be very modestly sized instances like an EC2 t2.micro or even a +nano. +For additional fault tolerance installations may use five meta nodes; the +number of meta nodes must be an odd number. + +Related entries: [meta service](#meta-service) + +### meta service - e + +The consistent data store that keeps state about the cluster, including which +servers, databases, users, continuous queries, retention policies, subscriptions, +and blocks of time exist. + +Related entries: [meta node](#meta-node) + +### metastore + +Contains internal information about the status of the system. +The metastore contains the user information, databases, retention policies, shard metadata, continuous queries, and subscriptions. + +Related entries: [database](/influxdb/v1.7/concepts/glossary/#database), [retention policy](/influxdb/v1.7/concepts/glossary/#retention-policy-rp), [user](/influxdb/v1.7/concepts/glossary/#user) + +### metric + +Measurements gathered at regular time intervals. + +### metric buffer - obsolete? + +The metric buffer caches individual metrics when writes are failing for an output plugin. +Telegraf will attempt to flush the buffer upon a successful write to the output. +The oldest metrics are dropped first when this buffer fills. + +Related entries: [output plugin](/telegraf/v1.10/concepts/glossary/#output-plugin) + +### missing value + +## N + +### node + +An independent `influxd` process. + +Related entries: [server](/influxdb/v1.7/concepts/glossary/#server) + +### now() + +The local server's nanosecond timestamp. + +### null + +## O + +### operator + +### option + +### option assignment + +### organization + +### output plugin + +Output plugins deliver metrics to their configured destination. In order to activate an output plugin, it needs to be enabled and configured in Telegraf's configuration file. + +Related entries: [aggregator plugin](/telegraf/v1.10/concepts/glossary/#aggregator-plugin), [flush interval](/telegraf/v1.10/concepts/glossary/#flush-interval), [input plugin](/telegraf/v1.10/concepts/glossary/#input-plugin), [processor plugin](/telegraf/v1.10/concepts/glossary/#processor-plugin) + +## P + +### parameter + +### pipe + +### pipe-forward operator + +### point + +The part of InfluxDB's data structure that consists of a single collection of fields in a series. +Each point is uniquely identified by its series and timestamp. + +You cannot store more than one point with the same timestamp in the same series. +Instead, when you write a new point to the same series with the same timestamp as an existing point in that series, the field set becomes the union of the old field set and the new field set, where any ties go to the new field set. +For an example, see [Frequently Asked Questions](/influxdb/v1.7/troubleshooting/frequently-asked-questions/#how-does-influxdb-handle-duplicate-points). + +Related entries: [field set](/influxdb/v1.7/concepts/glossary/#field-set), [series](/influxdb/v1.7/concepts/glossary/#series), [timestamp](/influxdb/v1.7/concepts/glossary/#timestamp) + +## points per second - in 1.x - obsolete? + +A deprecated measurement of the rate at which data are persisted to InfluxDB. +The schema allows and even encourages the recording of multiple metric values per point, rendering points per second ambiguous. + +Write speeds are generally quoted in values per second, a more precise metric. + +Related entries: [point](/influxdb/v1.7/concepts/glossary/#point), [schema](/influxdb/v1.7/concepts/glossary/#schema), [values per second](/influxdb/v1.7/concepts/glossary/#values-per-second) + +### precision + +The precision configuration setting determines how much timestamp precision is retained in the points received from input plugins. All incoming timestamps are truncated to the given precision. +Telegraf then pads the truncated timestamps with zeros to create a nanosecond timestamp; output plugins will emit timestamps in nanoseconds. +Valid precisions are `ns`, `us` or `µs`, `ms`, and `s`. + +For example, if the precision is set to `ms`, the nanosecond epoch timestamp `1480000000123456789` would be truncated to `1480000000123` in millisecond precision and then padded with zeroes to make a new, less precise nanosecond timestamp of `1480000000123000000`. +Output plugins do not alter the timestamp further. The precision setting is ignored for service input plugins. + +Related entries: [aggregator plugin](/telegraf/v1.10/concepts/glossary/#aggregator-plugin), [input plugin](/telegraf/v1.10/concepts/glossary/#input-plugin), [output plugin](/telegraf/v1.10/concepts/glossary/#output-plugin), [processor plugin](/telegraf/v1.10/concepts/glossary/#processor-plugin), [service input plugin](/telegraf/v1.10/concepts/glossary/#service-input-plugin) + +### process + +### processor plugin + +Processor plugins transform, decorate, and filter metrics collected by input plugins, passing the transformed metrics to the output plugins. + +Related entries: [aggregator plugin](/telegraf/v1.10/concepts/glossary/#aggregator-plugin), [input plugin](/telegraf/v1.10/concepts/glossary/#input-plugin), [output plugin](/telegraf/v1.10/concepts/glossary/#output-plugin) + +### Prometheus format + +## Q + +### query + +An operation that retrieves data from InfluxDB. +See [Data Exploration](/influxdb/v1.7/query_language/data_exploration/), [Schema Exploration](/influxdb/v1.7/query_language/schema_exploration/), [Database Management](/influxdb/v1.7/query_language/database_management/). + +## R + +### REPL + +### record + +### regular expressions + +### replication factor (RF) - e + +The attribute of the retention policy that determines how many copies of the +data are stored in the cluster. +InfluxDB replicates data across `N` data nodes, where `N` is the replication +factor. + +