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• State size increase
• Up to a couple of GB per task (especially painful on IO bound clusters)
• Depends on the actual policy used (probably UNALIGNED_WITH_MAX_INFLIGHT_DATA  is the more plausible default)
• Longer and heavier recovery depending on the increased state size
• Can potentially trigger death spiral after a first failure
• More up-to-date checkpoints will most likely still be an improvement about the current checkpoint behavior during backpressure
• For the MVP
  • no re-scaling
  • max in-flight checkpoints = 1

Test Plan

• Correctness tests with induced failures
• Compare checkpoints times under backpressure with current state
• Compare throughput under backpressure with current state
• Compare progress under backpressure with frequently induced failures
• Compare throughput with no checkpointing

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