anchor.diff:  %% the CLog scan (see pvc_find_maxvc/3 in clocksi_readitem_server)
   %%
   -spec pvc_bypass_snapshot(clocksi_payload(), #mat_state{}) -> ok.
  -pvc_bypass_snapshot(Payload, #mat_state{
  -    snapshot_cache = SnapshotCache
  -}) ->
  -    #clocksi_payload{
  -        key = Key,
  -        snapshot_time = SnapshotTime,
  -        op_param = DownstreamOp
  -    } = Payload,
  +pvc_bypass_snapshot(Payload, #mat_state{snapshot_cache = SnapshotCache}) ->
  +    #clocksi_payload{key = Key,
  +                     op_param = DownstreamOp,
  +                     snapshot_time = SnapshotTime} = Payload,
   
       SnapshotDict = case ets:lookup(SnapshotCache, Key) of
           [] ->
  
positive.code:     ).
  
  -spec pvc_update(clocksi_payload()) -> ok | {error, reason()}.
  pvc_update(Payload = #clocksi_payload{
      key = Key
  }) ->
      IndexNode = log_utilities:get_key_partition(Key),
      riak_core_vnode_master:sync_command(
          IndexNode,
  
negative.code:             PrevSnapshotDict
      end,
  
      %% last_op_id is a placeholder value, we don't use this field in pvc
      Snapshot = #materialized_snapshot{last_op_id = 0,
                                        value = DownstreamOp},
  
      %% Store in an ordered fashion in the multi-version dict
      NextSnapshotDict = vector_orddict:insert_bigger(SnapshotTime, Snapshot, SnapshotDict),
  
  