why sending flowrule so slow??

[ace tac]

dear friends! needs help!!

i build an app to give flowrule to my p4 switch,but i find that when my app give the flowrule ,it takes like 5 seconds until that flowfule take effect(pretending add -> added).but what i am doing is delay sensitive.BTW my onos ping my p4 only cost 1 ms. so its onos's problem?how can i optimize this ? and env. ONOS + stratum(tofino p4 switch)