Thanks for reaching out. Semi-asynchronous does *not* refer to incremental checkpoints and Savepoints are always triggered as full snapshots (not incremental).
Earlier versions of the RocksDb state backend supported two snapshotting modes, fully and semi-asynchronous snapshots. Semi-asynchronous state snapshots for RocksDb have been removed a long time ago by Aljoscha in https://github.com/apache/flink/pull/2345 (FLINK-4340). The notes you are referencing were added around that time and I'm afraid they might have become mostly obsolete. I'm pulling in Aljoscha who should be able to give a definitive answer here. To make a long story short, it should simply work for you to upgrade from 1.11 to 1.12 via a Savepoint. Cheers, Ufuk On Wed, Jan 20, 2021, at 3:58 AM, 耿延杰 wrote: > Hi all, > > As flink doc says: > https://ci.apache.org/projects/flink/flink-docs-release-1.12/ops/upgrading.html#preconditions > >> We do not support migration for state in RocksDB that was checkpointed using >> `semi-asynchronous` mode. In case your old job was using this mode, you can >> still change your job to use `fully-asynchronous` mode before taking the >> savepoint that is used as the basis for the migration. > > So, my first question: > Is "semi-asynchronous" means "incremental checkpoint"? > > And second question: > If so, assume I'm using flink-1.11 and RocksDB with incremental asynchronous > checkpoint as state backend. > I should: > 1. take a savepoint for old version(flink-1.11), > 2. and change job to use "full asynchronous checkpoint" , > 3. restart old version(flink-1.11) job with new config (full asynchronous > checkpoint), > 4. then, take a savepoint > 5. and finally, stop old version(flink-1.11) and upgrade to flink-1.12 > > Whether I understand correctly? > > Best regards
