@borrrden: I figured out the problem. In a push replication, if a document fails to get pushed, the replication will continue with pushing newer documents (so far so good). On the next push replication it will start again from the sequence number of the old document which previously had a push failure. That’s great, assuming that the push failure was temporary and may succeed this time. But I have an old doc _local document, which sync gateway rejects correctly, because CB Lite should not have submitted it in the first place. This means every push replication gets progressively longer as more revisions get created, and the replicator never advances up the LastSequence checkpoint. Should I submit an issue, or does it fall under CB Lite on Android Xamarin fails to replicate when local DB is large · Issue #742 · couchbase/couchbase-lite-net · GitHub ?
Similarly if my sync function rejects an old document for some reason, the LastSequence checkpoint get stuck on that document, and replication will always restart from that sequence number.