[FLINK-13550][docs] Add docs
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+---
+title: "Flame Graphs"
+weight: 3
+type: docs
+aliases:
+ - /ops/debugging/flame_graphs.html
+ - /ops/debugging/flame_graphs
+---
+<!--
+Licensed to the Apache Software Foundation (ASF) under one
+or more contributor license agreements. See the NOTICE file
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+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.
+-->
+
+# Flame Graphs
+
+[Flame Graphs](http://www.brendangregg.com/flamegraphs.html) are a visualization that effectively surfaces answers to questions like:
+- Which methods are currently consuming CPU resources?
+- How does consumption by one method compare to the others?
+- Which series of calls on the stack led to executing a particular method?
+
+{{< img src="/fig/flame_graph_on_cpu.png" class="img-fluid" width="90%" >}}
+{{% center %}}
+Flame Graph
+{{% /center %}}
+
+Flame Graphs are constructed by sampling stack traces a number of times. Each method call is presented by a bar, where the length of the bar is proportional to the number of times it is present in the samples.
+
+Starting with Flink 1.13, Flame Graphs are natively supported in Flink. In order to produce a Flame Graph, navigate to the job graph of a running job, select an operator of interest and in the menu to the right click on the Flame Graph tab:
+
+{{< img src="/fig/flame_graph_operator.png" class="img-fluid" width="90%" >}}
+{{% center %}}
+Operator's On-CPU Flame Graph
+{{% /center %}}
+
+Apart from the On-CPU Flame Graphs, [Off-CPU](http://www.brendangregg.com/FlameGraphs/offcpuflamegraphs.html) and Mixed visualizations are available and can be switched between by using the selector at the top of the pane:
+
+{{< img src="/fig/flame_graph_selector.png" class="img-fluid" width="30%" >}}
+
+The Off-CPU Flame Graph visualizes blocking calls found in the samples. A distinction is made as follows:
+- On-CPU: `Thread.State` in **[RUNNABLE, NEW]**
+- Off-CPU: `Thread.State` in **[TIMED_WAITING, WAITING, BLOCKED]**
+
+{{< img src="/fig/flame_graph_off_cpu.png" class="img-fluid" width="90%" >}}
+{{% center %}}
+Off-CPU Flame Graph
+{{% /center %}}
+
+Mixed mode Flame Graphs are constructed from stack traces of threads in all possible states.
+
+{{< img src="/fig/flame_graph_mixed.png" class="img-fluid" width="90%" >}}
+{{% center %}}
+Flame Graph in Mixed Mode
+{{% /center %}}
+
+## Sampling process
+
+The collection of stack traces is done purely within the JVM, so only method calls within the Java runtime are visible (no system calls).
+
+Flame Graph construction is performed at the level of an individual [operator]({{< ref "docs/concepts/glossary" >}}#operator), i.e. all [task]({{< ref "docs/concepts/glossary" >}}#task) threads of that operator are sampled in parallel and their stack traces are combined.
+
+
+
+{{< hint info >}}
+**Note:**
+Stack trace samples from all threads of an operator are combined together. If a method call consumes 100% of the resources in one of the parallel tasks but none in the others, the bottleneck might be obscured by being averaged out.
+
+There are plans to address this limitation in the future by providing "drill down" visualizations to the task level.
+{{< /hint >}}
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