public void setMaxUndos(int maxUndos) {
		synchronized (snapshotLock) {
			synchronized (this) {
				maxCheckpoints = maxUndos < 0 ? DEFAULT_CHECKPOINT_COUNT : (maxUndos + 1);
				while (checkpointHeads.size() > maxCheckpoints) {
					packCheckpoints();
				}
				disposeRedoCheckpoints();
			}
		}
	}
Set the maximum number of undoable checkpoints maintained by buffer manager.
Existing redo checkpoints are cleared and the stack of undo checkpoints
will be reduced if maxUndos is less than the current setting.
@param maxUndos maximum number of undo checkpoints.  A negative
value restores the default value.
Ghidra/Framework/DB/src/main/java/db/buffers/BufferMgr.java