anchor.diff:          {ok, RiakObject, Manifests} ->
               case update(RcPid, Manifests, RiakObject, WrappedManifests, Bucket, Key) of
                   {ok, _, _} = Res ->
  -                    maybe_backpressure_sleep(riakc_obj:value_count(RiakObject)),
  -                    Res;
  +                    case maybe_backpressure_sleep(riakc_obj:value_count(RiakObject)) of
  +                        true ->
  +                            %% Backpressure sleep has been triggered. Current object
  +                            %% is to be discarded to prevent unnecessary interleaving
  +                            %% with other concurrent manifest updates while sleeping.
  +                            {ok, undefined, undefined};
  +                        false ->
  +                            Res
  +                    end;
                   OtherRes ->
                       OtherRes
               end;
  
positive.code:             {PutResult, undefined, undefined}
      end.
  
  maybe_backpressure_sleep(Siblings) ->
      BackpressureThreshold = riak_cs_config:get_env(
                                riak_cs, manifest_siblings_bp_threashold, 5),
      maybe_backpressure_sleep(Siblings, BackpressureThreshold).
  
  maybe_backpressure_sleep(Siblings, BackpressureThreshold)
    when Siblings < BackpressureThreshold ->
      ok;
  maybe_backpressure_sleep(Siblings, _BackpressureThreshold) ->
      MaxSleep = riak_cs_config:get_env(riak_cs, manifest_siblings_bp_max_sleep, 30*1000),
      Coefficient = riak_cs_config:get_env(riak_cs, manifest_siblings_bp_coefficient, 200),
  
negative.code:     SleepMS = crypto:rand_uniform(MeanSleepMS - Delta, MeanSleepMS + Delta),
      lager:debug("maybe_backpressure_sleep: Siblings=~p, SleepMS=~p~n", [Siblings, SleepMS]),
      ok = riak_cs_stats:update(manifest_siblings_bp_sleep, SleepMS * 1000),
      ok = timer:sleep(SleepMS),
      true.
  
  update(RcPid, OldManifests, OldRiakObject, WrappedManifests, Bucket, Key) ->
      NewManiAdded = riak_cs_manifest_resolution:resolve([WrappedManifests, OldManifests]),
  