Github user StephanEwen commented on the issue:
https://github.com/apache/flink/pull/1668
@senorcarbone I agree, let's fix the multiple checkpoints issue and do the
rest in FLIP-15
The other operators have a pretty simply way of doing this:
- for synchronous checkpointed operators, no need to do anything, the
synchronous part of one checkpoint is over when the next starts (because it is
synchronous ;-))
- for asynchronously checkpointed state, the state backend needs to be
able to hold multiple snapshots, which are saved by multiple background threads
- none of the operators deal with in-flight data, which makes their job
easy
Dealing with in-flight data probably means that you need to open a
ListState for each checkpoint that arrives and add the feed back values to each
state, until that particular checkpoints barrier comes back through the
feedback channel. I think that should be sufficient.
---
If your project is set up for it, you can reply to this email and have your
reply appear on GitHub as well. If your project does not have this feature
enabled and wishes so, or if the feature is enabled but not working, please
contact infrastructure at [email protected] or file a JIRA ticket
with INFRA.
---
