Disaggregated Coordinator

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Overview Presto’s architecture originally only supported a single coordinator and a pool of workers. This has worked well for many years but created some challenges. To overcome these challenges, we came up with a new design with a disaggregated coordinator that allows the coordinator to be horizontally scaled out across a single pool of workers….

Even Faster Unnest

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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…