private void startCheckpoint() {

		// Clear Redo checkpoints
		disposeRedoCheckpoints();

		// Create new checkpoint
		++currentCheckpoint;
		BufferNode head = new BufferNode(HEAD, currentCheckpoint);
		BufferNode tail = new BufferNode(TAIL, currentCheckpoint);
		head.nextInCheckpoint = tail;
		tail.prevInCheckpoint = head;
		checkpointHeads.add(head);

		// Set as current checkpoint
		currentCheckpointHead = head;

		// pack old checkpoint if necessary
		packCheckpoints();
	}
Create a new checkpoint node list.
The redo stack will be cleared.
Ghidra/Framework/DB/src/main/java/db/buffers/BufferMgr.java