You will learn how CERN has implemented an Apache Spark-based data pipeline to support deep learning research work in High Energy Physics (HEP). HEP is a data-intensive domain. For example, the amount of data flowing through the online systems at LHC experiments is currently of the order of 1 PB/s, with particle collision events happening every 25 ns. Filtering is applied before storing data for later processing. Improvements in the accuracy of the online event filtering system are key to optimize usage and cost of compute and storage resources. A novel prototype of event filtering system based on a classifier trained using deep neural networks has recently been proposed. This presentation covers how we implemented the data pipeline to train the neural network classifier using solutions from the Apache Spark and Big Data ecosystem, integrated with tools, software, and platforms familiar to scientists and data engineers at CERN. Data preparation and feature engineering make use of PySpark, Spark SQL and Python code run via Jupyter notebooks. We will discuss key integrations and libraries that make Apache Spark able to ingest data stored using HEP data format (ROOT) and the integration with CERN storage and compute systems. You will learn about the neural network models used, defined using the Keras API, and how the models have been trained in a distributed fashion on Spark clusters using BigDL and Analytics Zoo. We will discuss the implementation and results of the distributed training, as well as the lessons learned.
Luca is a data engineer at CERN with the Hadoop, Spark, streaming and database services. Luca has 18+ years of experience with architecting, deploying and supporting enterprise-level database and data services with a special interest in methods and tools for performance troubleshooting. Luca is involved in developing and supporting solutions and platforms for data analytics and machine learning for the CERN community, including LHC experiments, the accelerator sector and CERN IT and enjoys taking part and sharing knowledge with the open source data community at large.
Jiao Wang is a software engineer on the Big Data Technology team at Intel who works in the area of big data analytics. She is engaged in developing and optimizing distributed deep learning frameworks on Apache Spark.