~/talk

The internals of stateful stream processing in Spark Structured Streaming

Talkat DataXDay 2019 · on Thursday, 2019-06-27· [data-engineering]
links:none on file
slides:none on file

Covers state management in Spark Structured Streaming 2.4.3 with concrete APIs and demos: use of groupBy/rollup/cube, flatMapGroupsWithState for arbitrary stateful processing, GroupState/GroupStateTimeout, watermarks and output modes, and triggers (micro-batch vs continuous). Demonstrates MemoryStream demo with checkpointing and shows state stored as files on HDFS that can be inspected and even modified, notes default shuffle partitions = 200 (changed to 1 for demo), explains how watermarks and windowing bound state size and when state expires.

AI-written summary · about

  1. 0:00Introduction
  2. 1:03Overview
  3. 3:07About me
  4. 5:46Stack Overflow
  5. 8:19Spark Structured Streaming
  6. 13:20Stateful Stream Processing
  7. 21:20Swimming Aggregation
  8. 23:29Optimizing Queries
  9. 31:31Checkpoint Location
  10. 45:11Example
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