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Posted to commits@helix.apache.org by ki...@apache.org on 2013/05/08 00:09:33 UTC
git commit: Adding documentation for Distributed task DAG execution
Updated Branches:
refs/heads/master 3e801a25b -> b225d8b84
Adding documentation for Distributed task DAG execution
Project: http://git-wip-us.apache.org/repos/asf/incubator-helix/repo
Commit: http://git-wip-us.apache.org/repos/asf/incubator-helix/commit/b225d8b8
Tree: http://git-wip-us.apache.org/repos/asf/incubator-helix/tree/b225d8b8
Diff: http://git-wip-us.apache.org/repos/asf/incubator-helix/diff/b225d8b8
Branch: refs/heads/master
Commit: b225d8b8472743990edfe907d73a3cd27fc03dea
Parents: 3e801a2
Author: Kishore Gopalakrishna <g....@gmail.com>
Authored: Tue May 7 15:09:16 2013 -0700
Committer: Kishore Gopalakrishna <g....@gmail.com>
Committed: Tue May 7 15:09:16 2013 -0700
----------------------------------------------------------------------
recipes/task-execution/README.md | 154 ++++++++++-
recipes/task-execution/pom.xml | 3 +-
.../helix/taskexecution/TaskExecutionDemo.java | 5 +-
.../org/apache/helix/taskexecution/Worker.java | 9 +-
src/site/markdown/recipes/task_dag_execution.md | 204 +++++++++++++++
src/site/site.xml | 2 +
6 files changed, 361 insertions(+), 16 deletions(-)
----------------------------------------------------------------------
http://git-wip-us.apache.org/repos/asf/incubator-helix/blob/b225d8b8/recipes/task-execution/README.md
----------------------------------------------------------------------
diff --git a/recipes/task-execution/README.md b/recipes/task-execution/README.md
index 9bc6c90..f0474e4 100644
--- a/recipes/task-execution/README.md
+++ b/recipes/task-execution/README.md
@@ -17,18 +17,71 @@ specific language governing permissions and limitations
under the License.
-->
-Distributed task execution
-----------------------------
-Quick Demo
-==========
-This recipe is intended to demonstrate how task dependencies can be modeled using primitives provided by Helix. A given task can be run with desired parallelism and will start
-only when up-stream dependencies are met. The demo executes the task DAG described below using 10 workers. Although the demo starts the workers as threads, there is no requirement
-that all the workers need to run in the same process. In reality, these workers work on many different boxes on a cluster. When worker failures occur, Helix takes care of
-re-assigning a failed task partition to a new worker. This recipe makes use of redis as a task result store. Any backing store can be used with a suitable implementation of
-TaskResultStore. The demo populates the task result store with 10000 dummy impression events and dummy click events based on a click probability of 0.01. It then submits the task
-execution DAG which results in execution of tasks with specified parallelism. In order to run the demo, use the following steps
+# Distributed task execution
+
+
+This recipe is intended to demonstrate how task dependencies can be modeled using primitives provided by Helix. A given task can be run with desired parallelism and will start only when up-stream dependencies are met. The demo executes the task DAG described below using 10 workers. Although the demo starts the workers as threads, there is no requirement that all the workers need to run in the same process. In reality, these workers run on many different boxes on a cluster. When worker fails, Helix takes care of
+re-assigning a failed task partition to a new worker.
+
+Redis is used as a result store. Any other suitable implementation for TaskResultStore can be plugged in.
+
+### Workflow
+
+
+#### Input
+
+10000 impression events and around 100 click events are pre-populated in task result store (redis).
+
+* **ImpEvent**: format: id,isFraudulent,country,gender
+
+* **ClickEvent**: format: id,isFraudulent,impEventId
+
+#### Stages
+
++ **FilterImps**: Filters impression where isFraudulent=true.
+
++ **FilterClicks**: Filters clicks where isFraudulent=true
+
++ **impCountsByGender**: Generates impression counts grouped by gender. It does this by incrementing the count for 'impression_gender_counts:<gender_value>' in the task result store (redis hash). Depends on: **FilterImps**
+
++ **impCountsByCountry**: Generates impression counts grouped by country. It does this by incrementing the count for 'impression_country_counts:<country_value>' in the task result store (redis hash). Depends on: **FilterClicks**
+
++ **impClickJoin**: Joins clicks with corresponding impression event using impEventId as the join key. Join is needed to pull dimensions not present in click event. Depends on: **FilterImps, FilterClicks**
+
++ **clickCountsByGender**: Generates click counts grouped by gender. It does this by incrementing the count for click_gender_counts:<gender_value> in the task result store (redis hash). Depends on: **impClickJoin**
+
++ **clickCountsByGender**: Generates click counts grouped by country. It does this by incrementing the count for click_country_counts:<country_value> in the task result store (redis hash). Depends on: **impClickJoin**
+
++ **report**: Reads from all aggregates generated by previous stages and prints them. Depends on: **impCountsByGender, impCountsByCountry, clickCountsByGender,clickCountsByGender**
+
+
+### Creating DAG
+
+Each stage is represented as a Node along with the upstream dependency and desired parallelism. Each stage is modelled as a resource in Helix using OnlineOffline state model. As part of Offline to Online transition, we watch the external view of upstream resources and wait for them to transition to online state. See Task.java for additional info.
```
+
+ Dag dag = new Dag();
+ dag.addNode(new Node("filterImps", 10, ""));
+ dag.addNode(new Node("filterClicks", 5, ""));
+ dag.addNode(new Node("impClickJoin", 10, "filterImps,filterClicks"));
+ dag.addNode(new Node("impCountsByGender", 10, "filterImps"));
+ dag.addNode(new Node("impCountsByCountry", 10, "filterImps"));
+ dag.addNode(new Node("clickCountsByGender", 5, "impClickJoin"));
+ dag.addNode(new Node("clickCountsByCountry", 5, "impClickJoin"));
+ dag.addNode(new Node("report",1,"impCountsByGender,impCountsByCountry,clickCountsByGender,clickCountsByCountry"));
+
+
+```
+
+### DEMO
+
+In order to run the demo, use the following steps
+
+See http://redis.io/topics/quickstart on how to install redis server
+
+```
+
Start redis e.g:
./redis-server --port 6379
@@ -36,11 +89,15 @@ git clone https://git-wip-us.apache.org/repos/asf/incubator-helix.git
cd recipes/task-execution
mvn clean install package -DskipTests
cd target/task-execution-pkg/bin
-chmod +x task-exection-demo.sh
-./task-exection-demo.sh 2181 localhost 6379
+chmod +x task-execution-demo.sh
+./task-execution-demo.sh 2181 localhost 6379
```
+```
+
+
+
+-----------------+ +----------------+
@@ -69,6 +126,79 @@ chmod +x task-exection-demo.sh
|(parallelism=1) |
+-----------------------+
+```
(credit for above ascii art: http://www.asciiflow.com)
+### OUTPUT
+
+```
+Done populating dummy data
+Executing filter task for filterImps_3 for impressions_demo
+Executing filter task for filterImps_2 for impressions_demo
+Executing filter task for filterImps_0 for impressions_demo
+Executing filter task for filterImps_1 for impressions_demo
+Executing filter task for filterImps_4 for impressions_demo
+Executing filter task for filterClicks_3 for clicks_demo
+Executing filter task for filterClicks_1 for clicks_demo
+Executing filter task for filterImps_8 for impressions_demo
+Executing filter task for filterImps_6 for impressions_demo
+Executing filter task for filterClicks_2 for clicks_demo
+Executing filter task for filterClicks_0 for clicks_demo
+Executing filter task for filterImps_7 for impressions_demo
+Executing filter task for filterImps_5 for impressions_demo
+Executing filter task for filterClicks_4 for clicks_demo
+Executing filter task for filterImps_9 for impressions_demo
+Running AggTask for impCountsByGender_3 for filtered_impressions_demo gender
+Running AggTask for impCountsByGender_2 for filtered_impressions_demo gender
+Running AggTask for impCountsByGender_0 for filtered_impressions_demo gender
+Running AggTask for impCountsByGender_9 for filtered_impressions_demo gender
+Running AggTask for impCountsByGender_1 for filtered_impressions_demo gender
+Running AggTask for impCountsByGender_4 for filtered_impressions_demo gender
+Running AggTask for impCountsByCountry_4 for filtered_impressions_demo country
+Running AggTask for impCountsByGender_5 for filtered_impressions_demo gender
+Executing JoinTask for impClickJoin_2
+Running AggTask for impCountsByCountry_3 for filtered_impressions_demo country
+Running AggTask for impCountsByCountry_1 for filtered_impressions_demo country
+Running AggTask for impCountsByCountry_0 for filtered_impressions_demo country
+Running AggTask for impCountsByCountry_2 for filtered_impressions_demo country
+Running AggTask for impCountsByGender_6 for filtered_impressions_demo gender
+Executing JoinTask for impClickJoin_1
+Executing JoinTask for impClickJoin_0
+Executing JoinTask for impClickJoin_3
+Running AggTask for impCountsByGender_8 for filtered_impressions_demo gender
+Executing JoinTask for impClickJoin_4
+Running AggTask for impCountsByGender_7 for filtered_impressions_demo gender
+Running AggTask for impCountsByCountry_5 for filtered_impressions_demo country
+Running AggTask for impCountsByCountry_6 for filtered_impressions_demo country
+Executing JoinTask for impClickJoin_9
+Running AggTask for impCountsByCountry_8 for filtered_impressions_demo country
+Running AggTask for impCountsByCountry_7 for filtered_impressions_demo country
+Executing JoinTask for impClickJoin_5
+Executing JoinTask for impClickJoin_6
+Running AggTask for impCountsByCountry_9 for filtered_impressions_demo country
+Executing JoinTask for impClickJoin_8
+Executing JoinTask for impClickJoin_7
+Running AggTask for clickCountsByCountry_1 for joined_clicks_demo country
+Running AggTask for clickCountsByCountry_0 for joined_clicks_demo country
+Running AggTask for clickCountsByCountry_2 for joined_clicks_demo country
+Running AggTask for clickCountsByCountry_3 for joined_clicks_demo country
+Running AggTask for clickCountsByGender_1 for joined_clicks_demo gender
+Running AggTask for clickCountsByCountry_4 for joined_clicks_demo country
+Running AggTask for clickCountsByGender_3 for joined_clicks_demo gender
+Running AggTask for clickCountsByGender_2 for joined_clicks_demo gender
+Running AggTask for clickCountsByGender_4 for joined_clicks_demo gender
+Running AggTask for clickCountsByGender_0 for joined_clicks_demo gender
+Running reports task
+Impression counts per country
+{CANADA=1940, US=1958, CHINA=2014, UNKNOWN=2022, UK=1946}
+Click counts per country
+{US=24, CANADA=14, CHINA=26, UNKNOWN=14, UK=22}
+Impression counts per gender
+{F=3325, UNKNOWN=3259, M=3296}
+Click counts per gender
+{F=33, UNKNOWN=32, M=35}
+
+
+```
+
http://git-wip-us.apache.org/repos/asf/incubator-helix/blob/b225d8b8/recipes/task-execution/pom.xml
----------------------------------------------------------------------
diff --git a/recipes/task-execution/pom.xml b/recipes/task-execution/pom.xml
index a4b454f..486ced8 100644
--- a/recipes/task-execution/pom.xml
+++ b/recipes/task-execution/pom.xml
@@ -28,7 +28,6 @@ under the License.
<artifactId>task-execution</artifactId>
<packaging>jar</packaging>
- <version>1.2-SNAPSHOT</version>
<name>Apache Helix :: Recipes :: distributed task execution</name>
<dependencies>
@@ -124,7 +123,7 @@ under the License.
<programs>
<program>
<mainClass>org.apache.helix.taskexecution.TaskExecutionDemo</mainClass>
- <name>task-exection-demo</name>
+ <name>task-execution-demo</name>
</program>
</programs>
</configuration>
http://git-wip-us.apache.org/repos/asf/incubator-helix/blob/b225d8b8/recipes/task-execution/src/main/java/org/apache/helix/taskexecution/TaskExecutionDemo.java
----------------------------------------------------------------------
diff --git a/recipes/task-execution/src/main/java/org/apache/helix/taskexecution/TaskExecutionDemo.java b/recipes/task-execution/src/main/java/org/apache/helix/taskexecution/TaskExecutionDemo.java
index 2cd0933..b9c9d0d 100644
--- a/recipes/task-execution/src/main/java/org/apache/helix/taskexecution/TaskExecutionDemo.java
+++ b/recipes/task-execution/src/main/java/org/apache/helix/taskexecution/TaskExecutionDemo.java
@@ -31,7 +31,10 @@ import org.apache.commons.io.FileUtils;
import org.apache.helix.HelixManager;
import org.apache.helix.controller.HelixControllerMain;
import org.apache.helix.taskexecution.Dag.Node;
-
+/**
+ *
+ *
+ */
public class TaskExecutionDemo {
public static void main(String[] args) throws Exception {
http://git-wip-us.apache.org/repos/asf/incubator-helix/blob/b225d8b8/recipes/task-execution/src/main/java/org/apache/helix/taskexecution/Worker.java
----------------------------------------------------------------------
diff --git a/recipes/task-execution/src/main/java/org/apache/helix/taskexecution/Worker.java b/recipes/task-execution/src/main/java/org/apache/helix/taskexecution/Worker.java
index 64a59e2..95673ba 100644
--- a/recipes/task-execution/src/main/java/org/apache/helix/taskexecution/Worker.java
+++ b/recipes/task-execution/src/main/java/org/apache/helix/taskexecution/Worker.java
@@ -29,7 +29,14 @@ import org.apache.helix.manager.zk.ZNRecordSerializer;
import org.apache.helix.manager.zk.ZkClient;
import org.apache.helix.model.InstanceConfig;
import org.apache.helix.participant.StateMachineEngine;
-
+/**
+ * Generic Worker that is a HELIX Participant which on start up joins the cluster and
+ * waits for state transitions from Helix.<br/>
+ * This class takes taskfactory and taskresultstore as arguments.<br/>
+ * As part of state transition @see {@link TaskStateModel},
+ * it launches task corresponding to the resource id.
+ *
+ */
public class Worker implements Runnable {
private final String _zkAddr;
private final String _clusterName;
http://git-wip-us.apache.org/repos/asf/incubator-helix/blob/b225d8b8/src/site/markdown/recipes/task_dag_execution.md
----------------------------------------------------------------------
diff --git a/src/site/markdown/recipes/task_dag_execution.md b/src/site/markdown/recipes/task_dag_execution.md
new file mode 100644
index 0000000..f0474e4
--- /dev/null
+++ b/src/site/markdown/recipes/task_dag_execution.md
@@ -0,0 +1,204 @@
+<!---
+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.
+-->
+
+# Distributed task execution
+
+
+This recipe is intended to demonstrate how task dependencies can be modeled using primitives provided by Helix. A given task can be run with desired parallelism and will start only when up-stream dependencies are met. The demo executes the task DAG described below using 10 workers. Although the demo starts the workers as threads, there is no requirement that all the workers need to run in the same process. In reality, these workers run on many different boxes on a cluster. When worker fails, Helix takes care of
+re-assigning a failed task partition to a new worker.
+
+Redis is used as a result store. Any other suitable implementation for TaskResultStore can be plugged in.
+
+### Workflow
+
+
+#### Input
+
+10000 impression events and around 100 click events are pre-populated in task result store (redis).
+
+* **ImpEvent**: format: id,isFraudulent,country,gender
+
+* **ClickEvent**: format: id,isFraudulent,impEventId
+
+#### Stages
+
++ **FilterImps**: Filters impression where isFraudulent=true.
+
++ **FilterClicks**: Filters clicks where isFraudulent=true
+
++ **impCountsByGender**: Generates impression counts grouped by gender. It does this by incrementing the count for 'impression_gender_counts:<gender_value>' in the task result store (redis hash). Depends on: **FilterImps**
+
++ **impCountsByCountry**: Generates impression counts grouped by country. It does this by incrementing the count for 'impression_country_counts:<country_value>' in the task result store (redis hash). Depends on: **FilterClicks**
+
++ **impClickJoin**: Joins clicks with corresponding impression event using impEventId as the join key. Join is needed to pull dimensions not present in click event. Depends on: **FilterImps, FilterClicks**
+
++ **clickCountsByGender**: Generates click counts grouped by gender. It does this by incrementing the count for click_gender_counts:<gender_value> in the task result store (redis hash). Depends on: **impClickJoin**
+
++ **clickCountsByGender**: Generates click counts grouped by country. It does this by incrementing the count for click_country_counts:<country_value> in the task result store (redis hash). Depends on: **impClickJoin**
+
++ **report**: Reads from all aggregates generated by previous stages and prints them. Depends on: **impCountsByGender, impCountsByCountry, clickCountsByGender,clickCountsByGender**
+
+
+### Creating DAG
+
+Each stage is represented as a Node along with the upstream dependency and desired parallelism. Each stage is modelled as a resource in Helix using OnlineOffline state model. As part of Offline to Online transition, we watch the external view of upstream resources and wait for them to transition to online state. See Task.java for additional info.
+
+```
+
+ Dag dag = new Dag();
+ dag.addNode(new Node("filterImps", 10, ""));
+ dag.addNode(new Node("filterClicks", 5, ""));
+ dag.addNode(new Node("impClickJoin", 10, "filterImps,filterClicks"));
+ dag.addNode(new Node("impCountsByGender", 10, "filterImps"));
+ dag.addNode(new Node("impCountsByCountry", 10, "filterImps"));
+ dag.addNode(new Node("clickCountsByGender", 5, "impClickJoin"));
+ dag.addNode(new Node("clickCountsByCountry", 5, "impClickJoin"));
+ dag.addNode(new Node("report",1,"impCountsByGender,impCountsByCountry,clickCountsByGender,clickCountsByCountry"));
+
+
+```
+
+### DEMO
+
+In order to run the demo, use the following steps
+
+See http://redis.io/topics/quickstart on how to install redis server
+
+```
+
+Start redis e.g:
+./redis-server --port 6379
+
+git clone https://git-wip-us.apache.org/repos/asf/incubator-helix.git
+cd recipes/task-execution
+mvn clean install package -DskipTests
+cd target/task-execution-pkg/bin
+chmod +x task-execution-demo.sh
+./task-execution-demo.sh 2181 localhost 6379
+
+```
+
+```
+
+
+
+
+
+ +-----------------+ +----------------+
+ | filterImps | | filterClicks |
+ | (parallelism=10)| | (parallelism=5)|
+ +----------+-----++ +-------+--------+
+ | | | |
+ | | | |
+ | | | |
+ | | +------->--------v------------+
+ +--------------<-+ +------v-------+ | impClickJoin |
+ |impCountsByGender |impCountsByCountry | (parallelism=10) |
+ |(parallelism=10) |(parallelism=10) ++-------------------+-+
+ +-----------+--+ +---+----------+ | |
+ | | | |
+ | | | |
+ | | +--------v---------+ +-v-------------------+
+ | | |clickCountsByGender |clickCountsByCountry |
+ | | |(parallelism=5) | |(parallelism=5) |
+ | | +----+-------------+ +---------------------+
+ | | | |
+ | | | |
+ | | | |
+ +----->+-----+>-----------v----+<---------------+
+ | report |
+ |(parallelism=1) |
+ +-----------------------+
+
+```
+
+(credit for above ascii art: http://www.asciiflow.com)
+
+### OUTPUT
+
+```
+Done populating dummy data
+Executing filter task for filterImps_3 for impressions_demo
+Executing filter task for filterImps_2 for impressions_demo
+Executing filter task for filterImps_0 for impressions_demo
+Executing filter task for filterImps_1 for impressions_demo
+Executing filter task for filterImps_4 for impressions_demo
+Executing filter task for filterClicks_3 for clicks_demo
+Executing filter task for filterClicks_1 for clicks_demo
+Executing filter task for filterImps_8 for impressions_demo
+Executing filter task for filterImps_6 for impressions_demo
+Executing filter task for filterClicks_2 for clicks_demo
+Executing filter task for filterClicks_0 for clicks_demo
+Executing filter task for filterImps_7 for impressions_demo
+Executing filter task for filterImps_5 for impressions_demo
+Executing filter task for filterClicks_4 for clicks_demo
+Executing filter task for filterImps_9 for impressions_demo
+Running AggTask for impCountsByGender_3 for filtered_impressions_demo gender
+Running AggTask for impCountsByGender_2 for filtered_impressions_demo gender
+Running AggTask for impCountsByGender_0 for filtered_impressions_demo gender
+Running AggTask for impCountsByGender_9 for filtered_impressions_demo gender
+Running AggTask for impCountsByGender_1 for filtered_impressions_demo gender
+Running AggTask for impCountsByGender_4 for filtered_impressions_demo gender
+Running AggTask for impCountsByCountry_4 for filtered_impressions_demo country
+Running AggTask for impCountsByGender_5 for filtered_impressions_demo gender
+Executing JoinTask for impClickJoin_2
+Running AggTask for impCountsByCountry_3 for filtered_impressions_demo country
+Running AggTask for impCountsByCountry_1 for filtered_impressions_demo country
+Running AggTask for impCountsByCountry_0 for filtered_impressions_demo country
+Running AggTask for impCountsByCountry_2 for filtered_impressions_demo country
+Running AggTask for impCountsByGender_6 for filtered_impressions_demo gender
+Executing JoinTask for impClickJoin_1
+Executing JoinTask for impClickJoin_0
+Executing JoinTask for impClickJoin_3
+Running AggTask for impCountsByGender_8 for filtered_impressions_demo gender
+Executing JoinTask for impClickJoin_4
+Running AggTask for impCountsByGender_7 for filtered_impressions_demo gender
+Running AggTask for impCountsByCountry_5 for filtered_impressions_demo country
+Running AggTask for impCountsByCountry_6 for filtered_impressions_demo country
+Executing JoinTask for impClickJoin_9
+Running AggTask for impCountsByCountry_8 for filtered_impressions_demo country
+Running AggTask for impCountsByCountry_7 for filtered_impressions_demo country
+Executing JoinTask for impClickJoin_5
+Executing JoinTask for impClickJoin_6
+Running AggTask for impCountsByCountry_9 for filtered_impressions_demo country
+Executing JoinTask for impClickJoin_8
+Executing JoinTask for impClickJoin_7
+Running AggTask for clickCountsByCountry_1 for joined_clicks_demo country
+Running AggTask for clickCountsByCountry_0 for joined_clicks_demo country
+Running AggTask for clickCountsByCountry_2 for joined_clicks_demo country
+Running AggTask for clickCountsByCountry_3 for joined_clicks_demo country
+Running AggTask for clickCountsByGender_1 for joined_clicks_demo gender
+Running AggTask for clickCountsByCountry_4 for joined_clicks_demo country
+Running AggTask for clickCountsByGender_3 for joined_clicks_demo gender
+Running AggTask for clickCountsByGender_2 for joined_clicks_demo gender
+Running AggTask for clickCountsByGender_4 for joined_clicks_demo gender
+Running AggTask for clickCountsByGender_0 for joined_clicks_demo gender
+Running reports task
+Impression counts per country
+{CANADA=1940, US=1958, CHINA=2014, UNKNOWN=2022, UK=1946}
+Click counts per country
+{US=24, CANADA=14, CHINA=26, UNKNOWN=14, UK=22}
+Impression counts per gender
+{F=3325, UNKNOWN=3259, M=3296}
+Click counts per gender
+{F=33, UNKNOWN=32, M=35}
+
+
+```
+
http://git-wip-us.apache.org/repos/asf/incubator-helix/blob/b225d8b8/src/site/site.xml
----------------------------------------------------------------------
diff --git a/src/site/site.xml b/src/site/site.xml
index 9b15248..1bff519 100644
--- a/src/site/site.xml
+++ b/src/site/site.xml
@@ -71,6 +71,8 @@
<item name="Distributed lock manager" href="./recipes/lock_manager.html"/>
<item name="Rabbit MQ consumer group" href="./recipes/rabbitmq_consumer_group.html"/>
<item name="Rsync replicated file store" href="./recipes/rsync_replicated_file_store.html"/>
+ <item name="Service Discovery" href="./recipes/service_discovery.html"/>
+ <item name="Distributed task DAG Execution" href="./recipes/task_dag_execution.html"/>
</menu>
<menu name="Get Involved">