• Part 1: Monday January 30, 14:00-17:00, lab SU2
• Part 2: Tuesday January 31, 14:00-17:00, lab SU2

• Introduction

Today we will be using the Perl API (there is no need to study it now, the tutorial will explain it).

• Step 1: Setting the environment.

• Step 2: Input and output format, testing data.
• Step 3: Basic mapper.
• Step 4: Counters.
• Step 5: Basic reducer.

• Step 6: Running on cluster.
• Step 7: Dynamic Hadoop cluster for several computations.

From now on, run all examples using a one-machine cluster. Running the scripts locally without any cluster has several disadvantages, most notably having only one reducer per job.

Setup, cleanup
Multiple reducers + Partitions
Combiners, perl inplace
Work dir
Hadoop properties

N-grams
K-means and Iterations

• Further information