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1. Initial state:
   
   1. No concurrent ConsistentCut process is running.
   2. lastFinishedCutId holds previous ConsistentCutId, or null.
2. User starts a command for creating new incremental snapshot:
   1. Ignite node inits a DistributedProcess with special message holds new ConsistentCutId (goal is to notify every node in a cluster about running incremental snapshot).  
3. Process of creation of incremental snapshot can be started by two events (what will happen earlier):
   1. Receive the ConsistentCutId by discovery.
   2. Receive the ConsistentCutId by transaction message (Prepare, Finish)
4. On receiving the ConsistentCutId, every node: 
   1. Checks whether ConsistentCut has already started or finished for this ID, skip if it has.
   2. In the message thread atomically:
      1. creates new ConsistentCut future.
      2. creates committingTx (goal is to track COMMITTING transactions, that aren't part of IgniteTxManager#activeTx)
      3. starts signing outgoing messages with the ConsistentCutId.
   3. In the background thread:
      
      1. Creates a copy of IgniteTxManager#activeTx. Set listeners on those tx#finishFuture.
      2. Writes a ConsistentCutStartRecord  to WAL with the received ConsistentCutId.
      3. Creates a copy of committingTxs. Set listeners on those tx#finishFuture.
      4. Set committingTxs to null.
5. While the DistributedProcess  is running every node is signing output transaction messages:
   1. Prepare and Finish messages are signed with the ConsistentCutId (to trigger ConsistentCut  on remote node, if not yet).
   2. Finish messages are signed additionally with txCutId on the node that commits first (see below in Signing messages, if it's not null then transaction starts committing After Consistent Cut):
      1. For 2PC it is an originated node.
      2. For 1PC it is a backup node.
6. For every receiving FinishMessage it puts the transaction into committingTxs, and marks the transaction with extracted from the message txCutId.
7. For every listening transaction, the callback is called when transaction finished:
   

   1. check If transaction state is UNKNOWN or status is RECOVERY_FINISH, then complete ConsistentCut with exception.

   2. if tx#txCutId equals to local, then transaction put into after, otherwise it's put into before.
8. After every listening transaction finished:
   1. Writes a ConsistentCutFinishRecord  into WAL with the collections ( before, after ). 
   2. Completes ConsistentCut  future.
   3. Note, that it continues to sign messages even after local ConsistentCut finish.
9. After ConsistentCut finish, DistributeProcess automatically notifies a node-initiator about local procedure has finished.
10. After all nodes finished ConsistentCut, on every node:
    
    1. Updates lastFinishedCutId with the current.
    2. ConsistentCut  future becomes null.
    3. Stops signing outgoing transaction messages.
11. Node initiator checks that every node completes correctly.
    1. If any node complete exceptionally - complete Incremental Snapshot with exception.

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