|author||Kishore Gopalakrishna <email@example.com>||Thu Jan 03 00:01:55 2013 -0800|
|committer||Kishore Gopalakrishna <firstname.lastname@example.org>||Thu Jan 03 00:01:55 2013 -0800|
[S4-110] Formatting code to make the diff look better
Goal is to provide better partition management, fault tolerance and automatic rebalancing during cluster expansion.
Limitation in S4
Advantages of integrating with Apache Helix,
This is still in prototype mode.
This will install the helix jars into local repo
git clone git://github.com/apache/incubator-helix.git ./build or mvn clean install -Dmaven.test.exec.skip=true
Checkout the S4 integration with Helix code
git clone git://github.com/kishoreg/incubator-s4.git
./gradlew install ./gradlew s4-tools:installApp
Create the cluster, -nbNodes is just the number of s4 nodes that will be run. This will create two nodes localhost_12000 and localhost_12001
./s4 newCluster -c=cluster1 -nbNodes=2 -flp=12000
Create a task that processes events from stream(names). -id can be anything but should be unique within a cluster, for now id and stream name needs to be the same. p is the number of partitions, so in this case it distributes 6 partitions among two nodes. -r is the number of replica/standby needed for each partition. Note that, when a node fails its load would be distributed among remaining nodes. So even though theoretically its possible to have number of standby's as the number of nodes, the performance would be horrible. In general this can be decided based on the head room available in the cluster.
./s4 createTask -c=cluster1 -id=names -t=consumer -p=6 -r=1 -s=names
Generate a HelloWorld App
./s4 newApp myApp -parentDir=/tmp cd /tmp/myApp ./s4 s4r -a=hello.HelloApp -b=/tmp/myApp/build.gradle myApp
Deploy the App by providing the s4r. One can optionally provide the list of nodes where this App has to be deployed.
./s4 deployApp -c=cluster1 -s4r=/tmp/myApp/build/libs/myApp.s4r -appName=myApp -zk=localhost:2181
Start the two s4 nodes in two separate windows. Note we now need to specify the node id while starting. This allows nodes to associate with same partitions when they are re-started.
./s4 node -c=cluster1 -zk=localhost:2181 -id=localhost_12000 ./s4 node -c=cluster1 -zk=localhost:2181 -id=localhost_12001
Send some events to names stream. Notice that the partitions are divided among two nodes and each event is routed to appropriate node.
./s4 genericAdapter -c=cluster1 -s=names
Run the status tool to view the cluster state. It provide which nodes are up, what Apps are deployed, metadata about tasks like what stream is it processing how many partitions, which node is leader for each partition etc
./s4 status -c=cluster1
Add new nodes, deploy the app to new nodes and re-distribute the task amongst all nodes
./s4 addNodes -c=cluster1 -nbNodes=1 -flp=12002 ./s4 deployApp -c=cluster1 -s4r=/tmp/myApp/build/libs/myApp.s4r -appName=myApp -zk=localhost:2181 ./s4 rebalanceTask -c=cluster1 -id=names
The partitions get re-distributed among 3 nodes. Run the status tool, it should show the new nodes and partition status.
./s4 status -c=cluster1
S4 is a general-purpose, distributed, scalable, partially fault-tolerant, pluggable platform that allows programmers to easily develop applications for processing continuous unbounded streams of data.
S4 0.5.0 is a complete refactoring of the previous version of S4. It grounds on the same concepts (partitioning inspired by map-reduce, actors-like distribution model), but with the following objectives:
We added the following core features:
For the latest information about S4, please visit our website at:
and our wiki, at:
Currently the wiki contains the most relevant and up-to-date documentation.
Source code is available here: https://git-wip-us.apache.org/repos/asf?p=incubator-s4.git
This only applies if you checkout from the source repository or if you download a released source package.
We use gradle http://gradle.org as the build system.
This will build the packages and install the artifacts in the local maven repository.
This will build the tools so that you can drive the platform through the “s4” command.
If you have a source package:
If you have a binary package: