Cheng Lian

Software Engineer, Databricks

Cheng got in touch with Spark since late 2013 and joined Databricks in early 2014 as one of the main developers behind Spark SQL. Now he’s a committer of Apache Spark and Apache Parquet. His current areas of interest include databases and programming languages.

Past sessions

Summit 2019 Fast and Reliable Apache Spark SQL Engine

April 24, 2019 05:00 PM PT

Building the next generation Spark SQL engine at speed poses new challenges to both automation and testing. At Databricks, we are implementing a new testing framework for assessing the quality and performance of new developments as they produced. Having more than 1,200 worldwide contributors, Apache Spark follows a rapid pace of development. At this scale, new testing tooling such as random query and data generation, fault injection, longevity stress, and scalability tests are essential to guarantee a reliable and performance Spark later in production. By applying such techniques, we will demonstrate the effectiveness of our testing infrastructure by drilling-down into cases where correctness and performance regressions have been found early. In addition, showing how they have been root-caused and fixed to prevent regressions in production and boosting the continuous delivery of new features.

Summit 2017 Why You Should Care about Data Layout in the Filesystem

June 6, 2017 05:00 PM PT

Efficient data access is one of the key factors for having a high performance data processing pipeline. Determining the layout of data values in the filesystem often has fundamental impacts on the performance of data access. In this talk, we will show insights on how data layout affects the performance of data access. We will first explain how modern columnar file formats like Parquet and ORC work and explain how to use them efficiently to store data values. Then, we will present our best practice on how to store datasets, including guidelines on choosing partitioning columns and deciding how to bucket a table.
Session hashtag: #SFexp20