[BEAM-9308] Optimize state cleanup at end-of-window

• Type: Improvement
• Status: Open
• Priority: P3
• Resolution: Unresolved
• Component/s: runner-dataflow
• Assignee: Unassigned
• Reporter: Steve Niemitz
• Created: 13/Feb/20 16:29
• Updated: 04/Jun/22 15:27

Description

When using state with a large keyspace, you can end up with a large amount of state cleanup timers set to fire all 1ms after the end of a window.  This can cause a momentary (I've observed 1-3 minute) lag in processing while windmill and the java harness fire and process these cleanup timers.

By spreading the firing over a short period after the end of the window, we can decorrelate the firing of the timers and smooth the load out, resulting in much less impact from state cleanup.

Issue Links

• links to: GitHub Pull Request #10852