On Thu, Feb 9, 2023 at 10:45 AM Kyotaro Horiguchi <horikyota....@gmail.com> wrote: > > At Wed, 8 Feb 2023 09:03:03 +0000, "Hayato Kuroda (Fujitsu)" > <kuroda.hay...@fujitsu.com> wrote in > > Thank you for reviewing! PSA new version. > > + if (statusinterval_ms > 0 && diffms > statusinterval_ms) > > The next expected feedback time is measured from the last status > report. Thus, it seems to me this may suppress feedbacks from being > sent for an unexpectedly long time especially when min_apply_delay is > shorter than wal_r_s_interval. >
I think the minimum time before we send any feedback during the wait is wal_r_s_interval. Now, I think if there is no transaction for a long time before we get a new transaction, there should be keep-alive messages in between which would allow us to send feedback at regular intervals (wal_receiver_status_interval). So, I think we should be able to send feedback in less than 2 * wal_receiver_status_interval unless wal_sender/receiver timeout is very large and there is a very low volume of transactions. Now, we can try to send the feedback before we start waiting or maybe after every wal_receiver_status_interval / 2 but I think that will lead to more spurious feedback messages than we get the benefit from them. -- With Regards, Amit Kapila.
