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1. Initial state:
   1. Ignite WAL are in consistent state relatively to previous full or incremental snapshot.
   2. Every Ignite node has local ConsistentCut  future equals to null.
   3. Empty collection committingTxs  that goal is to track COMMITTING+ transactions, that aren't part of IgniteTxManager#activeTx.
2. User starts a command for creating new incremental snapshot:
   1. Ignite node inits a DistributedProcess with special message holds new ConsistentCutMarker .
3. Process of creation of incremental snapshot can be started by two events (what will happen earlier):
   1. Receive the ConsistentCutMarker by discovery.
   2. Receive the ConsistentCutMarker by transaction message (Prepare, Finish)
4. On receiving the marker, every node: 
   1. In message thread atomically: creates new ConsistentCut  future, creates committingTxs, starts signing outgoing messages with the ConsistentCutMarker .
   2. In background thread:
      1. Writes a ConsistentCutStartRecord  to WAL with the received ConsistentCutMarker .
      2. Collects active transactions - concat of IgniteTxManager#activeTx and committingTxs .
5. While global ConsistentCut  is running every node signs output transaction messages:
   1. Prepare messages signed with the ConsistentCutMarker  (to trigger ConsistentCut  on remote node, if not yet).
   2. Finish messages signed with the ConsistentCutMarker  (to trigger...) and transaction ConsistentCutMarker  (to notify nodes which side of cut this transaction belongs to).
   3. Finish messages is signed with transaction ConsistentCutMarker on node that commits first.
6. For every collected active transaction, node waits for Finish message, to extract the ConsistentCutMarker  and prepares before , after  collections:
   1. if received marker is null or differs from local, then transaction on before  side
   2. if received color equals to local, then transaction on after  side
7. After all transactions finished:
   1. Writes a ConsistentCutFinishRecord  into WAL with the collections ( before, after ). 
   2. Stops filling committingTxs .
   3. Completes ConsistentCut  future, and notifies a node-initiator about finishing local procedure (with DistributedProcess  protocol).
8. After all nodes finished ConsistentCut :
   1. every node stops signing outgoing transaction messages
   2. ConsistentCut  future becomes null.
   3. Node Ignite node now in the initial state again.

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