On Monday, February 6, 2023 6:34 PM Kuroda, Hayato <kuroda.hay...@fujitsu.com> wrote: > > while reading the code, I noticed that in pa_send_data() we set wait > > event to WAIT_EVENT_LOGICAL_PARALLEL_APPLY_STATE_CHANGE while > sending > > the message to the queue. Because this state is used in multiple > > places, user might not be able to distinguish what they are waiting > > for. So It seems we'd better to use WAIT_EVENT_MQ_SEND here which will > > be eaier to distinguish and understand. Here is a tiny patch for that. > > In LogicalParallelApplyLoop(), we introduced the new wait event > WAIT_EVENT_LOGICAL_PARALLEL_APPLY_MAIN whereas it is practically waits a > shared message queue and it seems to be same as WAIT_EVENT_MQ_RECEIVE. > Do you have a policy to reuse the event instead of adding a new event?
I think PARALLEL_APPLY_MAIN waits for two kinds of event: 1) wait for new message from the queue 2) wait for the partial file state to be set. So, I think introducing a new general event for them is better and it is also consistent with the WAIT_EVENT_LOGICAL_APPLY_MAIN which is used in the main loop of leader apply worker(LogicalRepApplyLoop). But the event in pg_send_data() is only for message send, so it seems fine to use WAIT_EVENT_MQ_SEND, besides MQ_SEND is also unique in parallel apply worker and user can distinglish without adding new event. Best Regards, Hou zj