Myria Local Installation

1. Preparation

Install Java 8

Make sure JAVA_HOME points to the JDK 8 home directory on your machine.

If not, install JDK 8 and set JAVA_HOME accordingly. On the Mac, you should set JAVA_HOME to the output of /usr/libexec/java_home -v 1.8:

$ export JAVA_HOME=$(/usr/libexec/java_home -v 1.8)
$ echo $JAVA_HOME

Install SQLite

Myria normally uses PostgreSQL as its local storage engine for production deployments, but can use SQLite instead in development mode. SQLite is pre-installed on many systems, but if not, most package managers support SQLite, e.g. Homebrew on the Mac:

brew install sqlite3

2. Setting up a local MyriaX deployment

Download and build Myria

Ensure that git is installed and run git clone, which creates a directory myria with the master branch checked out.

To build the Myria jars, run ./gradlew clean shadowJar check from within the myria directory. This creates a single build artifact, build/libs/myria-0.1-all.jar, which is deployed in the next step. Make sure this file exists before continuing.

(Optional) Copy and edit the deployment configuration file

A MyriaX deployment needs a deployment configuration file, always at myriadeploy/deployment.cfg. It specifies the details of the deployment, such as the worker hostnames and port numbers. The myriadeploy directory contains some example configuration files. For local deployment, you should use the example file deployment.cfg.local, which creates a local cluster with one coordinator process and two worker processes, and uses SQLite as the storage backend. You can also make your own changes to this file. If you don’t want to make any changes, the launch_local_cluster command will automatically copy it to the right location.

If you want to make changes to the local configuration file, copy it to the standard location:

cp myriadeploy/deployment.cfg.local myriadeploy/deployment.cfg

Make any changes you want to myriadeploy/deployment.cfg, and then proceed to the next step.

3. Running the cluster

Launch the cluster

To start the coordinator and worker processes, execute the following command from the myriadeploy directory:


You should see log output like the following:

INFO: REEF Version: 0.15.0
INFO  2016-07-08 14:39:15,859 [main] MyriaDriverLauncher - Submitting Myria driver to REEF...
INFO  2016-07-08 14:39:17,789 [org.apache.reef.wake.remote.impl.OrderedRemoteReceiverStage_Pull-pool-2-thread-1] MyriaDriverLauncher$RunningJobHandler - Myria driver is running...
INFO  2016-07-08 14:39:26,525 [org.apache.reef.wake.remote.impl.OrderedRemoteReceiverStage_Pull-pool-2-thread-2] MyriaDriverLauncher$JobMessageHandler - Message from Myria driver: Worker 0 ready
INFO  2016-07-08 14:39:26,527 [org.apache.reef.wake.remote.impl.OrderedRemoteReceiverStage_Pull-pool-2-thread-2] MyriaDriverLauncher$JobMessageHandler - Message from Myria driver: Master is running, starting 2 workers...
INFO  2016-07-08 14:39:31,528 [org.apache.reef.wake.remote.impl.OrderedRemoteReceiverStage_Pull-pool-2-thread-2] MyriaDriverLauncher$JobMessageHandler - Message from Myria driver: Worker 2 ready
INFO  2016-07-08 14:39:36,530 [org.apache.reef.wake.remote.impl.OrderedRemoteReceiverStage_Pull-pool-2-thread-2] MyriaDriverLauncher$JobMessageHandler - Message from Myria driver: Worker 1 ready
INFO  2016-07-08 14:39:36,532 [org.apache.reef.wake.remote.impl.OrderedRemoteReceiverStage_Pull-pool-2-thread-2] MyriaDriverLauncher$JobMessageHandler - Message from Myria driver: All 2 workers running, ready for queries...

Check the cluster status

Query which workers the master knows about.

$ curl localhost:8753/workers

Query which workers are alive. They should match the output of the previous command!

$ curl localhost:8753/workers/alive

4. Using the REST API

To execute queries, we send requests to the coordinator using the coordinator’s REST API. The coordinator takes query plans in JSON format as input.

We illustrate the basic functionality using examples in the directory jsonQueries/getting_started. The jsonQueries directory contains additional examples. The documentation of the full set of REST APIs can be found here.

Ingest a dataset

To ingest tables that are not very large, we can send the data directly to the coordinator through the REST API. Here we use ingest_smallTable.json as the example. As specified in ingest_smallTable.json, it ingests the text file smallTable with the following schema:

"columnTypes" : ["LONG_TYPE", "LONG_TYPE"],
"columnNames" : ["col1", "col2"]

To ingest the file (you will need to change the path to your source data file in ingest_smallTable.json):

cd jsonQueries/getting_started
vi ./ingest_smallTable.json
curl -i -XPOST localhost:8753/dataset -H "Content-type: application/json"  -d @./ingest_smallTable.json

To ingest a large dataset in parallel, one way is to use the load function in MyriaL, which generates a parallel ingest query plan automatically. You can also use it to ingest data from a URL, such as a location in HDFS or S3.

Run a query

curl -i -XPOST localhost:8753/query -H "Content-type: application/json"  -d @./global_join.json

The Datalog expression of this query is specified in global_join.json. The SQL equivalent is:

SELECT t1.col1, t2.col2
FROM smallTable AS t1, smallTable AS t2
WHERE t1.col2 = t2.col1;

This query writes results back to the backend storage in a relation called smallTable_join_smallTable. You should be able to find the resulting tables in your SQLite databases (using the sqlite3 command-line tool). The table name is specified in the DbInsert operator, which you can modify.

Download a dataset

curl localhost:8753/dataset/user-jwang/program-global_join/relation-smallTable_join_smallTable/data

This will download the table smallTable_join_smallTable in CSV format. JSON and TSV are also supported:

curl 'localhost:8753/dataset/user-jwang/program-global_join/relation-smallTable_join_smallTable/data?format=json'

curl 'localhost:8753/dataset/user-jwang/program-global_join/relation-smallTable_join_smallTable/data?format=tsv'

5. Using the MyriaWeb interface

Install the Google App Engine SDK

Download and install the Google App Engine SDK. Make sure the development server exists in your PATH:

$ which

Download and install myria-web

Clone the myria-web repository:

git clone

Set up the myria-web application:

cd myria-web
git submodule update --init --recursive
pushd submodules/raco
python install

Launch the myria-web application:

$ ./appengine                                                                                                                                                        
INFO     2016-07-08 22:57:28,888] Starting API server at: http://localhost:61792
INFO     2016-07-08 22:57:28,892] Starting module "default" running at: http://localhost:8080
INFO     2016-07-08 22:57:28,895] Starting admin server at: http://localhost:8000

If you have a port conflict with the default port 8080, you can specify an alternative port: --port <MY_CUSTOM_PORT> ./appengine

Launch the MyriaWeb interface

Point your browser to http://localhost:8080. Try running the sample queries in the “Examples” tab of the right-hand pane. Click on the “Datasets” menu of the navigation bar and try downloading a dataset.

6. Shutting down the cluster

To shut down the cluster, simply kill the process you started in step 3 (launch_local_cluster). All child processes, including the coordinator and worker processes, will be automatically terminated.

Questions and issues

If you run into a bug or limitation in Myria, feel free to create a new issue. For general questions, you can email the Myria users list.