knaufk commented on a change in pull request #8607: [FLINK-12652] [documentation] add first version of a glossary URL: https://github.com/apache/flink/pull/8607#discussion_r293327705
########## File path: docs/concepts/glossary.md ########## @@ -0,0 +1,166 @@ +--- +title: Glossary +nav-pos: 3 +nav-title: Glossary +nav-parent_id: concepts +--- +<!-- +Licensed to the Apache Software Foundation (ASF) under one +or more contributor license agreements. See the NOTICE file +distributed with this work for additional information +regarding copyright ownership. The ASF licenses this file +to you under the Apache License, Version 2.0 (the +"License"); you may not use this file except in compliance +with the License. You may obtain a copy of the License at + + http://www.apache.org/licenses/LICENSE-2.0 + +Unless required by applicable law or agreed to in writing, +software distributed under the License is distributed on an +"AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY +KIND, either express or implied. See the License for the +specific language governing permissions and limitations +under the License. +--> + +#### Flink Application Cluster + +A Flink Application Cluster is a dedicated [Flink Cluster](./glossary#flink-cluster) that only +executes a single [Flink Job](./glossary#flink-job). The lifetime of the +[Flink Cluster](./glossary#flink-cluster) is bound to the lifetime of the Flink Job. Formerly +Flink Application Clusters were also known as Flink Clusters in *job mode*. Compare to +[Flink Session Cluster](./glossary#flink-session-cluster). + +#### Flink Cluster + +The distributed system consisting of (typically) one Flink Master process and one or more Flink +Taskmanagers processes. + +#### Event + +An event is a statement about a change of the state of the domain modelled by the +application. Events can be input and/or output of a stream or batch processing application. +Events are special types of [records](./glossary#Record) + +#### ExecutionGraph + +see [Physical Graph](./glossary#physical-graph) + +#### Function + +Functions, or user-defined functions (UDFs), are implemented by the user and encapsulate the +application logic of a Flink program. Most Functions are wrapped by a corresponding +[Operator](./glossary#operator). + +#### Instance + +The term *instance* is used to describe a specific instance of a specific type (usually +[Operator](./glossary#operator) or [Function](./glossary#function)) during runtime. As Apache Flink +is mostly written in Java, this corresponds to the definition of *Instance* or *Object* in Java. +In the context of Apache Flink, the term *parallel instance* is also frequently used to emphasize +that multiple instances of the same [Operator](./glossary#operator) or +[Function](./glossary#function) type are running in parallel. + +#### Flink Job + +A Flink Job is the runtime representation of a Flink program. A Flink Job can either be submitted +to a long running [Flink Session Cluster](./glossary#flink-session-cluster) or it can be started as a +self-contained [Flink Application Cluster](./glossary#flink-application-cluster). + +#### JobGraph + +see [Logical Graph](./glossary#logical-graph) + +#### Flink JobManager + +JobManagers are one of the components running in the +[Flink JobManger Process](./glossary#flink-jobmanager-process). A JobManager is responsible for +supervising the execution of the [Tasks](./glossary#task) of a single job. + +#### Logical Graph + +A logical graph is a directed graph describing the high-level logic of a stream processing program. +The nodes are [Operators](./glossary#operator) and the edges indicate input/output-relationships or +data streams or data sets. + +#### Managed State + +Managed State describes application state which has been registered with the framework. For +Managed State, Apache Flink will take care about persistence and rescaling among other things. + +#### Flink JobManager Process + +The Job Manager Process is the master of a [Flink Cluster](./glossary#flink-cluster). It is called +*JobManager* for historical reasons, but actually has actually contains three distinct components: +Flink Resource Manager, Flink Dispatcher and one [Flink JobManager](./glossary#flink-jobmanager) +per running [Flink Job](./glossary#flink-job). + +#### Operator + +Node of a [Logical Graph](./glossary#logical-graph). An Operator performs a certain operation, +which is usually executed by a [Function](./glossary#function). Sources and Sinks are special +Operators for data ingestion and data egress. + +#### Operator Chain + +An Operator Chain consists of one or more consecutive [Operators](./glossary#operator) without any Review comment: Ok, personally I think a chain of size 1 is perfectly fine, but I'll change it ;) ---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: [email protected] With regards, Apache Git Services
