Tachyon quick start!!

Running Tachyon Locally

This guide describes how to accomplish the following:

• Run Tachyon on a single machine
• Set Apache HDFS as Tachyon’s underlayer filesystem
• Set Amazon S3 as Tachyon’s underlayer filesystem
• Hack away!!

Run Tachyon Standalone

The prerequisite for this part is that you have Java (JDK 6 or above).

Download the binary distribution of Tachyon 0.4.1:

$ wget http://tachyon-project.org/downloads/tachyon-0.4.1-bin.tar.gz
$ tar xvfz tachyon-0.4.1-bin.tar.gz
$ cd tachyon-0.4.1

Before executing Tachyon run scripts, requisite environment variables must be specified in conf /tachyon-env.sh, which should be created from the included template file:

$ cp conf/tachyon-env.sh.template conf/tachyon-env.sh

To run standalone mode, make sure that TACHYON_UNDERFS_ADDRESS in conf/tachyon-env.sh is set to a tmp directory in the local filesystem (e.g.,export TACHYON_UNDERFS_ADDRESS=/tmp).

Then, you can format Tachyon FileSystem and start it. Note: since Tachyon needs to setup RAMfs, starting a local system requires users to input their root password for Linux based users.

$ ./bin/tachyon format
$ ./bin/tachyon-start.sh local

To verify that Tachyon is running, you can visit http://localhost:19999, or see the log in the folder tachyon/logs. You can also run a sample program:

$ ./bin/tachyon runTest Basic CACHE_THROUGH

For the first sample program, you should be able to see something similar to the following:

/Basic_File_CACHE_THROUGH has been removed
2014-02-02 09:32:02,760 INFO   (TachyonFS.java:connect) - Trying to connect master @ localhost/127.0.0.1:19998
2014-02-02 09:32:02,791 INFO   (MasterClient.java:getUserId) - User registered at the master localhost/127.0.0.1:19998 got UserId 10
2014-02-02 09:32:02,792 INFO   (TachyonFS.java:connect) - Trying to get local worker host : hy-ubuntu
2014-02-02 09:32:02,800 INFO   (TachyonFS.java:connect) - Connecting local worker @ hy-ubuntu/127.0.1.1:29998
2014-02-02 09:32:02,819 INFO   (CommonUtils.java:printTimeTakenMs) - createFile with fileId 18 took 60 ms.
2014-02-02 09:32:03,194 INFO   (TachyonFS.java:createAndGetUserTempFolder) - Folder /mnt/ramdisk/tachyonworker/users/10 was created!
2014-02-02 09:32:03,198 INFO   (BlockOutStream.java:) - /mnt/ramdisk/tachyonworker/users/10/19327352832 was created!
Passed the test!

To run a more comprehensive sanity check:

$ ./bin/tachyon runTests

Set HDFS as Tachyon’s under filesystem

The additional prerequisite for this part is Hadoop HDFS. By default, Tachyon is set to use HDFS version 1.0.4. You can use another Hadoop version by changing the hadoop.version tag in pom.xml in Tachyon and recompiling it. You can also set the hadoop version when compiling with maven:

$ mvn -Dhadoop.version=2.2.0 clean package

Edit tachyon-env.sh file. Setup TACHYON_UNDERFS_ADDRESS=hdfs://HDFS_HOSTNAME:HDFS_IP. You may also need to setup JAVA_HOME in the same file.

Set Amazon S3 as Tachyon’s under filesystem

Edit tachyon-env.sh file. Setup TACHYON_UNDERFS_ADDRESS=s3://s3address and the necessary credentials such as fs.s3n.awsAccessKeyId andfs.s3n.awsSecretAccessKey under TACHYON_JAVA_OPTS. You may also need to setup JAVA_HOME in the same file.
and VOILA!!!