Even Faster Unnest

Unnest is a common operation in Facebook’s daily Presto workload. It converts an ARRAY, MAP, or ROW into a flat relation. Its original implementation used deep copy all the time and was very inefficient. In Unnest Operator Performance Enhancement with Dictionary Blocks, the author improved the Unnest operator by up to 10x in CPU and…

Running Presto in a Hybrid Cloud Architecture

Migrating SQL workloads from a fully on-premise environment to cloud infrastructure has numerous benefits, including alleviating resource contention and reducing costs by paying for computation resources on an on-demand basis. In the case of Presto running on data stored in HDFS, the separation of compute in the cloud and storage on-premises is apparent since Presto’s…