[IGNITE-20052] Release all locks locally on self primary replica expiration

• Type: Improvement
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 3.0.0-beta2
• Labels: ignite-3 transaction3_recovery transactions
• Epic Link: Tx on unstable topology: commit partition recovery
• Assignee: Vladislav Pyatkov
• Reporter: Alexander Lapin
• Reviewer: Kirill Sizov
• Created: 26/Jul/23 07:14
• Updated: 28/Sep/23 09:11
• Resolved: 28/Sep/23 09:10

Description

Motivation

It is not only useless, but also harmful to keep locks on an expired primary because corresponding commitTimestamps are either calculated or the transaction will be aborted.

Definition of Done

• All local partition specific locks are released on self primary replica expiration.

Implementation Notes

• It's required to introduce local onPrimaryExpired callback.
• An open question here is how to detect whether a given primary hosted any locks.
• We've discussed and agreed that the following test should be written. It might not be the only one to write, however it's definitely useful.
  • Start two nodes A and B with partition P1 on node A and partition P2 on node B.
  • Begin transaction Tx1 on node B.
  • Touch P2 on B
  • Touch P1 on A
  • Kill Node B, meaning kill Tx coordinator, commit partition and P2.
  • Discard P1 lease prolongation.
  • Await P1 lease expiration and check that locks were released.
• In order to discard lease prolongation, we may add special placement driver methods that will add an ability to discard or transfer lease. At least they'll be useful within testing.
• We've agreed that we may duplicate org.apache.ignite.internal.table.distributed.raft.PartitionListener#txsPendingRowIds in order to have it in PartitionReplicaListener. That will allow us to handle primaryReplica.onExpired() in a following way (pseudocode)

  txsPendingRowIds.keySet().forEach(txId -> lockManager.unlock(txId))

  Besides that, given map is required in order to cleanup writeIntents on primary if primary isn't a part of a replication group.

• Seems that we don't need the whole map, but only the keySet, meaning txIds. Because corresponding value Set<RowId> is used in order to cleanup writeIntetns and the only case why we need rowIds on primary explicitly is when primary itself ins't the part of replication group. And if it's true rebalance engine will drop the whole old primary local partition with all corresponding write intents.

Issue Links

• is blocked by: IGNITE-19570 Write intent resolution for RW transactions
• links to: GitHub Pull Request #2620