Recovery types • Precise recovery (exactly-once) • It hides the effects of a failure perfectly • Post-failure output is identical to no-failure 8 Vasiliki Kalavri | Boston University 2020 Recovery Recovery types • Precise recovery (exactly-once) • It hides the effects of a failure perfectly • Post-failure output is identical to no-failure • Rollback recovery (at-least-once) • It avoids information Recovery types • Precise recovery (exactly-once) • It hides the effects of a failure perfectly • Post-failure output is identical to no-failure • Rollback recovery (at-least-once) • It avoids information

amount of memory off heap. To understand how much memory RocksDB might use, you can checkout this blog post8 by Stefan Richter. 4.13.1.1 Key Metrics Metric Scope Description Status.JVM.Memory.NonHeap be very helpful in setups without existing host monitoring capabilities. 4.15 Conclusion This post tries to shed some light on Flink’s metrics and monitoring system. You can utilise it as a starting your application, and learn much more about Flink’s internals early on. Last but not least, this post only scratches the surface of the overall metrics and monitoring capabilities of Apache Flink. I

• An event is pre-snapshot if it occurs before the local snapshot on a process, otherwise it is post- snapshot • If event A happens causally before B and B is pre-snapshot, then A is also pre-snapshot • An event is pre-snapshot if it occurs before the local snapshot on a process, otherwise it is post- snapshot • If event A happens causally before B and B is pre-snapshot, then A is also pre-snapshot • An event is pre-snapshot if it occurs before the local snapshot on a process, otherwise it is post- snapshot • If event A happens causally before B and B is pre-snapshot, then A is also pre-snapshot

an underlying graph structure 5 Edge events: A purchase, a movie rating, a like on an online post, a bitcoin transaction, a packet routed from a source to destination Vertex events: A new product

partitioned by key • State can be cleared based on watermarks or punctuations • window fires, post becomes inactive 41 Vasiliki Kalavri | Boston University 2020 case class Reading(id: String, time:

partitioned by key • State can be cleared based on watermarks or punctuations • window fires, post becomes inactive ??? Vasiliki Kalavri | Boston University 2020 Operator selectivity 6 • The number